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Learn about the different methods of communication using physical and digital ways of transferring data. Based on the 2016 OCR Cambridge Technicals Level 3 IT specification. 2.5 & 4.2: Communication Methods Exam Board: OCR Specification: 2016 - Unit 1 Sections 2.5 and 4.2 are very similar so both are mixed within this page. There are many ways that employees of a business can communicate between staff members or with their customers . Text-based Communication Letter ✓ It is a traditional method of communication that can be used for formal occasions such as job offers or resignations . ✓ It can be kept and stored for physical evidence - e.g. keeping an applicant's CV in case an opportunity arises in the future. X Requires postage costs to be sent in the mail (a first-class stamp is now £1.65 ). Overseas delivery is even more expensive . X Takes several days time to be received in the post and may be lost . X A letter can't include certain formats like video. Text Message (SMS) ✓ Can reach a large audience at once with one batch message . ✓ Good for short messages - e.g. appointment reminders or confirmation codes for two-factor authentication . ✓ Doesn't require an internet connection to receive messages. X Limited to short messages (160 characters ) with no multimedia . X Text messages can cost to send each message. SMS stands for Short Message Service . Email ✓ Easily send information to many people at once, instantly . ✓ Can include documents , multimedia attachments and links . ✓ Can send targeted emails to customers on a mailing list with new products or sales promotions . X Important messages may be lost in the spam folder. X Phishing scams can spread malware via email attachments. Instant Messaging ✓ Works in real-time - messages are sent and received instantly . ✓ Attachments and hyperlinks can be sent. ✓ Can be used by support staff to help customers in real-time. X Quick speed means it's less suitable for formal conversations like interviews. X Internet access issues will disrupt any conversations . Voice-based Communication Cellular ✓ Can hear how something is said , unlike text responses. ✓ Fastest method of communication - also allows reactive conversations that can quickly change based on previous responses. X Impacted by cellular reception - won't work in remote areas / underground. X Can't see the other person's body language, presentation or facial expressions. Teleconferences ✓ Allows for groups of people to communicate at once . ✓ Businesses can use teleconferencing to communicate between offices / individuals across the world . X The quality of the call may be affected by a group's poor reception . X Because a group is communicating, people may speak over each other , especially if there is a time delay . VoIP (Voice over Internet Protocol) ✓ Allows a user to make calls over the internet (e.g. using WhatsApp). ✓ Cheaper (can also be free) to make calls rather than using a cellular network . X Relies on a good-quality internet connection . X Can potentially be less secure than cellular connections. hi there Personal Assistants ✓ Speeds up processes by making appointments, checking information or connecting to smart devices. ✓ Voice-activated - can be used whilst otherwise busy , such as typing, cooking or driving. ✓ The language can be changed to suit people's preferences. X Huge privacy concerns as companies store audio data for voice recognition and track all commands made to the device. X There may be recognition issues as sometimes the assistant doesn't understand a command . Online Communication Video Conferences ✓ Users can connect to the call (e.g. using Zoom, Skype, or Google Meet) remotely , saving time and money instead of all travelling to one location. ✓ Can be used for interviews as it allows the applicant and the interviewers to see each other and look for body language . ✓ Users can share information visually , such as designs. X A high-bandwidth connection is required to send and receive video data reliably . X A poor internet connection (e.g. a weak WiFi signal ) will result in low-quality video that may stutter or drop out , making it hard to communicate clearly . Social Media ✓ Businesses can quickly share information with a large online audience , including new potential customers . ✓ Posts can be in d i fferent formats such as text, images, videos or links to other websites. ✓ Direct messages sent on social media may be seen and responded to faster than alternatives like using email if push notifications are enabled on a phone. ✓ Some social media sites like Facebook allow for private , invite-only groups to communicate with like-minded users in a secure way. X Businesses must be cautious about what they post so as not to accidentally offend others and damage their reputation . X Social media posts and customer comments must be carefully managed , so a social media manager should be hired. Blog / Vlog ✓ Share information with followers in text , images and video formats . ✓ Blogs and vlogs can unite people with similar interests , such as a cookery blog or travel vlog. ✓ Companies can use a blog to promote new products and provide details of upcoming events to try and attract new customers . X Takes a lot of effort and time to create posts, especially editing videos for vlogs. X Bad behaviour or language in vlogs can bring punishment. Several YouTubers have lost their reputations following videos they have posted. Q uesto's Q uestions 2.5 & 4.2 - Communication Methods: 1. Describe three advantages and three disadvantages for each type of communication method . You will need to think of or research some more than the examples listed on this page. a. Letter b. SMS (Text Message) c. Email d. Instant Message e. Cellular Call f. Teleconference g. VoIP Call h. Personal Assistant i. Video Conference j. Social Media k. Blog / Vlog [6 each ] 2. Explain what VoIP stands for and what it allows a user to do. [ 2 ] 3. Describe which communication method would be most appropriate for the following scenarios and why : a. Informing your boss you are going to resign. b. Communicating with management about raising your pay. c. Chatting to team members about when the Christmas party is. d. Sending promotions to thousands of customers. e. Interviewing a potential new employee who is in a different country. f. Talking with a group of investors about the company's latest data. [2 each ] 2.6 - Software Troubleshooting 2.4 Operating Systems 4.1 Communication Skills 4.3 - Personal Attributes Topic List

Learn about the characteristics of information and the impacts of both good and poor quality information on customers and stakeholders. Based on the 2016 OCR Cambridge Technicals Level 3 IT specification for Unit 2 (Global Information). 2.3 - Quality of Information Exam Board: OCR Specification: 2016 - Unit 2 Information Characteristics Valid Information This is correct, up-to-date and complete information that fits its purpose . For example, detailed end-of-year financial data in the form of graphs. Biased Information This is technically correct, but slanted , information that presents a one-sided view . For example, end-of year financial data that focuses on profits and ignores significant losses. Relevant Information Information should be appropriate for the required purpose . Irrelevant information may get in the way of correct decision making. Accurate Information Information should be carefully selected and entirely correct , inaccurate information can lead to unwanted consequences such as higher costs and missed deadlines. Reliable Information Information from a source that can be verified and confirmed to be correct . For example, BBC News is a more reliable information source than social media posts. Information Quality The quality of information that an organisation uses will have a significant impact on further processes and decisions. Good quality information that is accurate , valid or reliable can lead to better strategic decisions , meeting deadlines and innovation . Poor quality information that is biased , inaccurate or out of date may lead to negative consequences such as loss of customer trust , fines and legal challenges . Positive Effects of Good Quality Information Reliable information received by the management team . Good quality research information. Good quality sales information. Accurate cost projection information. Informed decisions with a higher chance of success . Can lead to innovation and better understanding . Strategic decisions and planning ahead . Projects will stay within their budget . Accurate time expectations . Projects will be completed on time . Negative Effects of Poor Quality Information Biased survey with inaccurate results . Inaccurate stock information. Out of date information received by management . Inaccurate data has led to poor reviews online . Inaccurate time expectations . Misinformed decisions , not responding to customers needs . ??? Inaccurate delivery times , customers unhappy . Too much / little stock. Miss out on opportunities , possible fall in profits . Loss of customer trust , loss of customers and reputation . Financial issues . Projects take longer , cost more , stakeholders unhappy . Possible project failure . Q uesto's Q uestions 2.3 - Quality of Information: 1. Describe 5 characteristics of information . [10 ] 2. Explain 5 positive impacts of good quality information . [10 ] 3. Explain 5 negative impacts of poor quality information . [10 ] 2.2 - Information Classification 2.4 - Information Management Topic List

Learn about searching algorithms such as linear and binary search. Also learn about sorting algorithms such as merge, bubble and insertion sorts. Based on the J277 OCR GCSE Computer Science specification (first taught from 2020 onwards). 1.3: Searching & Sorting Algorithms Exam Board: OCR Specification: J277 Watch on YouTube : Linear Search Binary Search Bubble Sort Merge Sort Insertion Sort Key features of a bubble sort: Uses an outer while loop (condition controlled ) to check no swaps have been made . Uses an inner for loop (count controlled ) to repeat through the length of the data set . Uses a flag (a Boolean value ) to track if a swap has been made and uses a temporary value to help correctly swap elements . Linear Search A linear search is the most simple search algorithm. Each data item is searched in order from the first value to the last as if they were all laid out in a line . The list does not have to be in any order before it is searched . This search is also known as a sequential search because the list is searched in a sequence from start to end. For large lists , this search is not very efficient . Binary Search A binary search is a much more efficient searching algorithm as it generally searches through fewer data and is often much quicker - especially for large data sets . In a binary search, the middle point of the data is selected with each iteration and compared to the value being searched for . When the midpoint matches the target value , it as been found and the search can stop. ! ! However there is a prerequisite of using a binary search - the list of data must already be sorted . A prerequisite is a condition that must be satisfied before an algorithm will work correctly . Merge Sort Merge sort is a sorting algorithm based on the idea of ‘divide and conquer ’. A merge sort divides a list into half , again and again until each data item is separate . Then the items are combined in the same way as they were divided , but now in the correct order . When the individual lists are all merged together as one list again, then the data is in order and the algorithm will end . Bubble Sort This algorithm is based on the comparison of adjacent data elements . Data elements are swapped if they are not in the correct order . The algorithm will only stop when a complete iteration through the data is completed with no swaps made . A bubble sort is not suitable for large sets of data . Insertion Sort The list is logically split into sorted values (on the left) and unsorted values (on the right). Starting from the left, values from the unsorted part are checked and inserted at the correct position in the sorted part. This continues through all elements of the list until the last item is reached, and sorted. Insertion sorts are efficient for small data sets but would be slow to sort large sets , compared to alternatives such as a merge sort. Key features of a linear search: A loop is used to check the first value in a list and increment by 1 , checking each value for a match to the target . Reaching the last element of the list without finding a match means the value is not included . Key features of a binary search: A midpoint , lowpoint and highpoint are calculated . A while loop is used to repeatedly compare the midpoint to a target value . The upper half or lower half of the data is ignored if the midpoint does not equal the target . Key features of a merge sort: This algorithm calls itself from within the subroutine (this is known as a recursive algorithm ). It continually splits sublists into a left side and a right side until each sublist has a length of 1 . Watch on YouTube Watch on YouTube Watch on YouTube Watch on YouTube Key features of a insertion sort: Uses an outer for loop (count controlled ) to iterate through each value in the list . Uses an inner while loop (condition controlled ) to find the current value’s correct position in the sorted part of the list . An insertion sort moves ‘ backwards ’ to find the correct position of each value, by decreasing the index within the while loop. Watch on YouTube Q uesto's Q uestions 1.3 - Searching & Sorting Algorithms: Linear Search Explain step-by-step how the number 8 would be found in the following list using a linear search : 12, 5, 3, 2, 8, 19, 14, 6 [4 ] Binary Search Explain step-by-step how the number 2 would be found in the following list using a binary search : 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 [6 ] Merge Sort Explain step-by-step how a merge sort would sort the following list of numbers: 4, 8, 5, 1, 3, 6, 7, 2 [6 ] Bubble Sort Explain step-by-step how a bubble sort would sort the following list of numbers: 3, 1, 6, 5, 2, 4 [6 ] Insertion Sort Explain step-by-step how an insertion sort would sort the following list of numbers: 5, 2, 6, 3, 1, 4 [6 ] 1.2 - Designing Algorithms Theory Topics 2.1 - Programming Fundamentals

Learn how to link to other websites by using the anchor tag. 4. Hyperlinks HTML Guide Watch on YouTube: A hyperlink is a link to another web page . In this section, you will link your page to a real website, like Wikipedia. Hyperlinks require the anchor tags and Copy a URL Firstly you need to copy the full web address of the web page that you would like to link your page to. Choose an appropriate web page that relates to your chosen topic. Create the Anchor Tag 4. Close the start of the tag . 1. Open the start of the tag . 2. Type href (stands for hypertext reference ). 3. Paste the URL inside speech marks . 5. Type the text you want the user to click on . 6. Time to close the tag . When you save your webpage and run it in a browser you will be able to click highlighted text to open the website you have chosen. Add at least three different hyperlinks to your webpage. Try to add the 2nd & 3rd links without looking at this page - practise makes perfect. Add a Hyperlink within a Sentence You can also create an anchor tag within a sentence. Hyperlinks are important to link webpages together. Next is time for adding pictures! Either change one of your previous hyperlinks to be in the middle of a sentence or create a new one. 3. Text Tags HTML Guide 5. Images

The final part of a quick guide to the basics of Python aimed at Key Stage 3 students. Learn about importing turtle to command a moving object. Python - Iteration For Loops Editor Execute A for loop is a count controlled loop. It repeats for a certain number of times as stated in the range brackets. The first number (1) states the number to start on . The second number is an exclusive end . This means it actually finishes on the number before . (11 will end on 10). You need a colon at the end of the loop line . Each line to be repeated must be indented (press the tab key). You can use the loop number within the loop itself. 1. Write a for loop to print your name 8 times . (Count it to double-check it prints eight times.) 2. Use a for loop to print each number between 10 and 50 . 3. Use a for loop from 1 to 10 . Print the 3 times table by multiplying number by 3 underneath the loop. 4. Ask the user to input a whole number (call it num1 ). Write num1 in your range brackets to repeat any message that many times. 5. Ask the user to input a whole number (call it num1 ) and then input a word . Print the word by the number they entered . (Hint: Use num1 in the range.) 6. Delete your code and copy these 3 lines: #Delete the space after the colon for number in range(0,21,2): print(number) What happens when you run this code? 7. Use Q6 to help you print 0 to 100 , going up in 5s . Think about the 3 values you need in the range brackets. 8. Use Q6 to help you print 100 down to 0 , backwards by 1 . Think about the 3 values you need in the range brackets. Tasks While Loops Editor Execute A while loop is a condition controlled loop . While loops repeat as long as the condition is true . As soon as the condition becomes false , the loop will end . 1. Change the program in the editor to repeat the loop while a number is not equal to 33 . 2. Make a new while loop that asks the user to enter a whole number . While the number is less than or equal to 1000 , keep repeating. 3. Make a new while loop for while a colour is not equal to purple (or any colour you want). Ask the user to enter a colour inside of the loop . Don't forget to set colour to "" before you start. 4. Edit your colour program to count how many guesses were made. Make a new variable called count and set it to 0 at the start of the program. Increase it by 1 in the loop, using count = count + 1 . 5. While a total is less than 100 , ask the user to input a decimal number . When it is over 100 , print ‘COMPUTER OVERLOAD’ . You need a variable called total . Increase the total each time with total = total + number . Don't forget to start it at 0 . Tasks != means ‘not equal to ’. The loop below will repeat as long as the password is not equal to “abc123” . Any variable you use in your condition must have a value first . You can’t check for your password if it doesn’t exist. That’s why I have written password = “” , to give password a value before we check it .

Learn how to play sound files in Greenfoot. Part 5 of the Greenfoot Tutorial for the Eduqas / WJEC GCSE 2016 specification. 5. Play Sounds 1. Check the Sounds Folder Greenfoot Tutorial Sound files must be placed the ' sounds ' folder of your Greenfoot project to be used in the game. In the Component 2 exam of the WJEC / Eduqas 2016 specification , an audio file will be placed in the sounds folder already . For this example game you can download the audio clips to the right and paste them into your sounds folder . Watch on YouTube: Click the audio icon to download a zip folder of the two sound files below . Copy the files into the sounds folder of your Greenfoot project . < Part 4 - Remove Objects 2. Add the playSound Method Add the code to play the sound at the same time as when the collectible object is removed . The name of the file and its extension (e.g. .wav or .mp3 ) must be written in speech marks after the playSound method. Part 6 - The Counter >

The final part of a quick guide to the basics of Python aimed at Key Stage 3 students. Learn about importing turtle to command a moving object. Python - #6 - Turtle Import the Turtle The turtle library stores all of the code to create and move an object called a turtle . The turtle library must be imported into your Python program before you can use it to draw lines, shapes and colours . Create a new Python program and save the file as PythonTurtle . Write import turtle as the first line of code. Basic Shapes The turtle can be controlled by writing how many pixels it should travel forward and the angle it should point left or right . Moving Forwards turtle.forward(100) will move the turtle forward by 100 pixels. turtle.forward(200) will move the turtle forward by 200 pixels. When using the left command or the right command, the turtle won't actually move , but it will rotate by the number of degrees that you state. For example, typing turtle.left(90) will point the turtle upwards . Rotating Left & Right Copy the code to the right to make the turtle draw a square. Then try to make: A Rectangle A Triangle A Pentagon A Hexagon Square Rectangle Triangle Pentagon Hexagon Hint: To work out the angles, divide 360 by the number of sides. Using Loops You can use a for loop to repeat code . This is especially helpfully with intricate shapes with many sides. The code below will print a square but in only 3 lines instead of the 8 lines from task 2. This is the number of times the code underneath will be repeated . Change it to a higher number to repeat it more often . Each line after the 'for num in range' line must be indented . Press the tab key once on your keyboard to indent your code. Task 3 - Copy the code above to make the turtle draw a square using a loop. Then try to make: A Heptagon An Octagon A Circle A Pentagram (5-sided Star) Square Heptagon Octagon Circle Pentagram Hint: To work out the angles, divide 360 by the number of sides. Advanced Features Choose a background colour turtle .bgcolor("red") Choose the line size and colour turtle.pensize(6) turtle.color("green") Fill a shape turtle.color("yellow") turtle.begin_fill() (put your turtle's directions in here) turtle.end_fill() Lift the pen turtle.penup() turtle.pendown() Speed up/Slow down the turtle turtle.speed(speed=10) Change the turtle's appearance turtle.shape("turtle") Other options include "circle" and "arrow". Task 4 - Use the code above to make: A blue square on a red background. A yellow triangle on a pink background. Two different coloured circles - not touching each other. Three different shapes of three different colours - not touching each other. Complex Shapes Use everything that you have learned on this page to help you create more complex shapes. You could try: A Flower A Word (like your name - you will need to use the penup() and pendown() commands. A Christmas tree A Landscape (green ground, blue sky, yellow sun) <<< Selection

Learn about the different types of LAN, MAN and WAN networks and how to draw network diagrams. Based on the 2016 OCR Cambridge Technicals Level 3 IT specification. 3.4 - Connection Methods Exam Board: OCR Specification: 2016 - Unit 1 Local Area Network (LAN) A Local Area Network (LAN ) is a network in which the computer systems are all located geographically close to each other , for example, in the same building or on the same site , like a school or office . A type of LAN is a Wired Ethernet LAN ( technically Ethernet is a protocol that controls how data is transmitted over a LAN). Wired Ethernet LANs have a high bandwidth so data can be transferred quickly and because it uses cables the data is harder to intercept than a wireless network. Metropolitan Area Network (MAN) A Metropolitan Area Network (MAN ) connects several LANs together to cover the range of a town or city , for example a university campus network. MANs are usually very efficient at providing fast communication for cities , with high connection speeds through the use of fibre optic cables. Wide Area Network (WAN) A Wide Area Network (WAN ) is a network spanning a large geographical area , such as multiple cities or countries . The internet is the ultimate example of a WAN as it stretches across the entire world. Different types of WAN rules and standards are used: ADSL ADSL ( Asymmetric Digital Subscriber Line ) is a method of transferring data across copper wire telephone lines . ADSL is contended, which means that connection speeds are affected and slowed down by more systems that use the network at the same time . The old copper wires also affect data transfer over long distances and can cause data packet loss . Security is also an issue, as the line is shared with others, making data interception more likely . To improve security, a firewall and/or VPN (Virtual Private Network) may be used. Because ADSL uses the telephone system, a modem is require d at both the sending and receiving ends of the connection. A microfilter is also required to allow internet and telephone access at the same time . ADSL is contended - shared between sites. Internet Service Provider ADSL requires a modem Leased Line Leased Line is a method of providing an uncontended , fixed-bandwidth data connection . The user maintains a dedicated connection that is more secure and, because it is uncontended , will have the same speed all of the time , regardless of how busy the network is . Bandwidth is high , security is better , the connection speed is constant and the network is full-duplex (allowing for data transmission both ways simultaneously). These advantages come at a high cost - possibly hundreds of pounds per month - as well as an expensive installation that can take time to be put in place . As it is a complex configuration , a CSU/DSU (Channel Service Unit/Data Service Unit) device is required to properly terminate the leased line . Internet Service Provider Leased Line is dedicated. C A CSU/DSU is required for a leased line. ISDN ISDN (Integrated Services Digital Network ) transmits video and voice data simultaneously over traditional copper telephone wires . This method uses a circuit-switched network where all data packets take the same route between computer systems. Voice Networks Voice networks primarily transfer audio data using phones and telephone lines . PSTN PSTN (Public Switched Telephone Network ) is the global collection of wired public telephone networks that are used to transmit data over a long distance. PSTN is fixed into position using underground cables and therefore the connection quality is much more consistent than other voice networks. Using a wired connection like a PSTN is more reliable and communication will be clearer than alternatives such as cellular or satellite methods. Cellular Cellular networks require a cell tower (also called a transmitting tower ) to be in close proximity to the communication device. Cellular networks have a greater range than PSTN, but buildings and poor weather can disrupt this point-to-point communication method (where line of sight is necessary ). Each cell tower is also connected to the PSTN . Satellite Satellite networks use point-to-multipoint communication by using satellites above the Earth's atmosphere that receive a transmission and rebroadcast them back to Earth. Because of the distance between the communication device and the satellite (potentially thousands of miles ), there is a delay between data transmission and it being received . Satellite networks are beneficial in remote locations , such as natural disaster zones , where the cell tower may not be present or may be damaged. Transmitting large files using satellites may take longer , and it is not recommended for low-latency needs such as video gaming. There are different types of satellites used in communication and networking : Geostationary satellites are used for consistent communication over a specific region , such as TV broadcasts and weather monitoring . They can also be used to transfer data between remote locations . Low-Earth orbiting satellites are closer to the ground so they enable fast communication for internet services . Medium-Earth orbiting satellites are often used for GPS (Global Positioning System ) and other navigation systems . A global positioning satellite is an example of this type of satellite that provides time and geolocation data to GPS receivers back on Earth. Diagrammatical Representation In an exam, you may be asked to draw a diagram representing how networks are connected . This is different from drawing a network topology (e.g. ring or mesh) and refers to: Connection type (e.g. ADSL / Leased Line). Devices (e.g. router / modem), Security methods (e.g. firewall / VPN) Two LANs connected using a Leased line Two LANs connected using an ADSL line Rules for drawing a network diagram: Label each device and label your LANs . Use appropriate symbols and be neat . There are no set symbols, just be consistent (e.g. both modems are the same shape). ADSL must have a modem and VPN router + Firewall . (ADSL is not very secure so it needs to be protected with the VPN router and firewall. It also uses the telephone line across the internet so it requires a modem at both ends). Leased Line must have a router , a direct connection and CSU/DSU . (Leased line is a secure and direct connection - so it doesn’t need a firewall or VPN router and should be direct (not across the internet )). Q uesto's Q uestions 3.4 - Connection Methods: 1a. What is the definition of a LAN ? [ 2 ] 1b. Describe two benefits of using a wired Ethernet LAN . [ 4 ] 2. What is the definition of a MAN ? [ 2 ] 3a. What is the definition of a WAN ? [ 2 ] 3b. What is the difference between a contended and an uncontended network? [ 2 ] 3 c. Describe the differences between a leased line and ADSL . You should discuss security , connection speed and contention ( contended or uncontended ) . [6 ] 3d. Describe the use of any two network devices required for either a leased line and/or for ADSL . [ 4 ] 3e. Describe the purpose of ISDN . [ 2 ] 4a. Compare the use of PSTN and Cellular methods to make telephone calls . [ 4 ] 4b. Explain 1 way that a satellite network should be used and 1 way it shouldn't be used . [ 4 ] 5. Draw a diagram to show how a leased line or ADSL network can be set up between two existing LANs. [6 ] 3.3 - Network Characteristics Topic List 3.5 - Business Systems

Learn about the three types of translators - assemblers, interpreters and compilers. Also, understand the differences between compilers and interpreters. Based on the 2020 Eduqas (WJEC) GCSE specification. 10.1: Translators Exam Board: Eduqas / WJEC Specification: 2020 + What is a translator? A translator changes (translates) a program written in one language into another language (usually machine code ). There are three types of translator : Assembler An assembler converts low level assembly language into machine code . INP STA 33 INP STA 34 LDA 33 ADD OUT HLT Interpreter An interpreter converts high-level language one line at a time into machine code and executes it. PYT HON Compiler A compiler converts high-level language into machine code for execution at a later time. The entire program is converted at once . PYT HON 0010 1011 0101 0101 0110 0111 0101 0001 0101 0101 0010 1011 0101 0101 0110 0111 0101 0001 0101 0101 0010 1011 0101 0101 0110 0111 0101 0001 0101 0101 Differences between an interpreter and a Compiler: Interpreter Compiler Execution Method: An interpreter translates source code (high level code) into machine code one line at a time . Execution Speed: An interpreter is slower than a compiler because the code must be reinterpreted each time the program is run. Complexity: Interpreters are smaller, simpler programs . Error Reporting: In error reporting, the interpreter would encounter the errors and report it to the user immediately and stops the program from running. Repetition: Interpreted programs can be edited and run without translating the whole program . Interpreters must reinterpret the program every time it is run. Execution Method: A compiler translates all the source code (high level code) into machine code in one go . A compiler produces an executable file that will run on other machines without the compiler needing to be installed. Execution Speed: Compilers can produce much more efficient code than interpreters making the compiled programs run faster . Complexity: Compilers tend to be large complex programs . Error Reporting: The compiler would analyse the entire program , taking note of where errors have occurred and record them in an error file . Repetition: Compilation requires analysis and the generation of the code only once , whereas interpreters must re-interpret each time. However, compiled programs have to be re-compiled after any changes have been made. x1 ∞ x1 Q uesto's Q uestions 10.1 - Translators: 1. Briefly describe each type of translator : a. Assembler [ 1 ] b. Interpreter [ 2 ] c. Compiler [ 2 ] 2. Compare interpreters and compilers for each of the following features : a. Execution Method b. Execution Speed c. Complexity d. Error Reporting e. Repetition [ 10 total ] 9.1 - IDE Tools Theory Topics 10.2 - Stages of Compilation

Learn about the purpose and characteristics of intranets, the internet and extranets - all three types of World Wide Web technologies. Based on the 2016 OCR Cambridge Technicals Level 3 IT specification for Unit 2 (Global Information). 1.5 - WWW Technologies Exam Board: OCR Specification: 2016 - Unit 2 The internet is a global network of interconnected networks . The world wide web (WWW ) is not the same as the internet. It is a way of accessing information , using protocols such as HTTPS to view web pages . There are three types of world wide web technologies : Internet Intranet Extranet The internet i s a global network of interconnected networks . The internet is public and users have open access . Examples of use: Accessing web pages to shop and watch videos . Businesses may use web pages to advertise their products and allow customers to purchase items. An intranet is a private network that is only accessible to authorised users (e.g. members of a business or school). Intranets are private and users have closed access . Examples of use: Because an intranet is a secured online area , schools often use an intranet to log in to that displays information for teachers and students (such as test results or upcoming events ). Businesses might use an intranet for employees to see sales and performance data or for communication because it can be accessed remotely . An extranet is a private network that is accessible using the internet but provides access only to authorised users . Extranets are private and users have shared access . Example of use: Hotel booking companies (like booking.com) use an extranet to allow hotel owners to log in via the internet to access and update their information. Network Characteristics When connecting to WWW technologies there are several characteristics that a user must consider: Speed Speed refers to how quickly data can be accessed . For example, an extranet is the slowest network to use because it must be accessed through the internet first. Security Security relates to how likely the data will be kept secure . An intranet is more secure than the internet because only authorised users can log in. Access Levels Access levels , or permissions , refers to who can see what, in terms of data and files . Resources on an intranet can be set so that only certain users can view them. Accessibility This characteristic relates to how available the data is . For example, the internet can be accessed on any network-enabled device, at any time . Q uesto's Q uestions 1.5 - WWW Technologies: 1. Explain the difference between the internet and the world wide web . [2 ] 2. Describe each of the 3 types of WWW technology . You must mention whether they are private or public and what type of access they have. a. Internet b. Intranet c. Extranet [2 each ] 3. Describe at least one example of how each of the 3 types of WWW technology could be used . [6 ] 4. Describe the 3 WWW technologies in terms of each of the 4 network characteristics . You need to think carefully about this; the descriptions under each icon above can help you with certain answers. To start, describe the speed, security, access levels and accessibility of an intranet . [12 each ] 1.4 - Internet Connections Topic List 1.6 - Information Formats

Learn about the benefits of compression and the differences between lossy and lossless compression. Also, learn how compression ratios work. Based on the 2020 Eduqas (WJEC) GCSE specification. 4.8: Compression Exam Board: Eduqas / WJEC Specification: 2020 + What is compression? To compress a file means to make its size smaller . Benefits of compression include: Files take up less storage space (so more files can be stored). Files can be transferred quicker (because they are smaller). Files can be read from or written to quicker . There are two methods that are used to compress files: Lossy and Lossless . Lossy Compression Lossy compression uses an algorithm (set of instructions) to analyse a file and remove data that cannot be heard or seen by humans . For example, a lossy algorithm would analyse the sound waves of an audio file and remove any frequencies which humans cannot hear. This process reduces the size of the file . Further lossy compression will remove data that humans can see / hear . For example, the dog image to the right has been strongly compressed using a lossy algorithm and some data has clearly been removed. Lossy compression removes the data permanently , so the file can never return to its original form . Lossy compression is often used with images , audio and video to reduce the file size, for example to send over the internet. Lossless Compression Lossless compression reduces the size of a file without permanently removing any data . Because of this, the file is returned to its original form when decompressed, so no quality is lost . A file that is compressed with a lossless algorithm is usually larger than a file compressed with a lossy algorithm because no data has been permanently removed. Lossless compression is used with files that would not work if data was removed, for example executable files (e.g. programs and games) or word documents . Remember that lossy and lossless compression do not just refer to images. Below is an audio file that has been compressed with lossy compression . Data has been removed so the audio quality has decreased. 197 KB 81 KB 43 KB Compression Ratios Original File Size Compression Ratio = Compressed File Size 4 Mb = 5:1 20 Mb Example: A file has been compressed from 20 megabytes down to 4 megabytes. This is a compression ratio of 5:1. To calculate the size after compression , divide the original size by the first ratio value, then multiply it by the second value. For example, the new size for file 1 is (210 ÷ 10) x 3 = 63 MB. Triple-click the final column to see the right answers. Q uesto's Q uestions 4.8 - Compression: 1. Describe 3 benefits of compressing a file . [ 3 ] 2. Describe the differences between lossy and lossless compression . [4 ] 3. A student needs to compress a Microsoft Word document to send in an email. Suggest which type of compression they should use and why . [ 2 ] 4a. A text file was 72 KB and was compressed to 8 KB . State the compression ratio . 4b. An audio file was 4.5 MB and has been compressed to 0.9 MB. State the ratio. 4c. A 20 MB file is compressed with a ratio of 5:2 . What is the size of the compressed file ? [ 1 each ] 63MB 164KB 96KB 4.7 Sound Representation Theory Topics 5.1 - Data Structures

Learn about different types of hardware that allow data to be sent between systems, including router, modem, bridge and WAP. Based on the 2016 OCR Cambridge Technicals Level 3 IT specification. 1.5: Communication Hardware Exam Board: OCR Specification: 2016 - Unit 1 The devices on this page are used to create or link together networks , allowing data to be sent between computer systems . Hub A hub receives data packets from a connected device and transfers a copy to all connected nodes . Switch A switch receives data packets , processes them and transfers them on to the device s pecifically listed in the destination address of the packet. Modem Modems are used to send data across the telephone network . The telephone lines can only transfer analog signals so a modem is used to convert a computer's digital data into an analog signal . Another modem converts the signal back to a digital format at the receiving end. Router Routers are used to transfer data packets between networks . Data is sent from network to network on the internet towards the destination address listed in the data packet. A router stores the address of each computer on the network and uses routing tables to calculate the quickest and shortest path . Wireless Access Point (WAP) Provides a link between wireless and wired networks . It creates a wireless local area network that allows WiFi enabled devices to connect to a wired network. Combined Device Also known as a hybrid device , this provides the functionality of multiple communication devices (e.g modem, router, switch and/or wireless access point) in a single device . They can be more expensive than a single device but are more adaptable - if the routing part of the device fails it might still be able to function as a switch / wireless access point etc. However, you will see an increased performance from a standalone device rather than a combined one as standalone devices have more complex features (e.g. VPN support). Network Interface Card (Network Adapter) A Network Interface Card (often shorted to NIC ) is an internal piece of hardware that is required for the computer to connect to a network . It used to be a separate expansion card but now it is commonly built directly into the motherboard (and known as a network adapter ). Wireless network interface cards allow wireless network connection. Q uesto's Q uestions 1.5 - Communication Hardware: 1. What is the difference between a hub and a switch ? [2 ] 2. Explain how a modem works. [3 ] 3. Explain the purpose of a router . [2 ] 4. What is a Wireless Access Point (WAP )? [2 ] 5. Describe what is meant by a 'combined device '. Give one advantage and one disadvantage of using a combined device. [3 ] 1.4 - Connectivity 1.6 - Hardware Troubleshooting Topic List