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The fifth part of a quick guide to the basics of Python aimed at Key Stage 3 students. Learn about how selection works and how to use if statements. Python - #5 - Selection 1. Using if Statements Using if enables your program to make a choice . There are a few things you need to remember : if is lowercase - it should turn orange. You must use double equals == You need a colon : at the end of your if line. The line below your if line must be indented . Task 1 - Create a new Python program and save the file as 5-Selection.py Use the picture to help you ask what your favourite food is . Run the program and test it works. To indent a line press the tab key on your keyboard. Indentation is important as it tells Python what is within the if statement and what isn't. 2. Using elif elif stands for 'else if '. It is used to respond in a different way depending on the input. elif works exactly the same as an if line so if you make a mistake look up at task 1 to help you. Task 2 - Write an elif line that responds differently to your favourite food question from task 1. e.g. "Yum!" if someone enters "pasta". 3. Using else It is impractical to have hundreds of elif lines to respond to different inputs. else is used to respond to anything else that has been entered in a general way. The else line works a bit differently, so look carefully at the picture . Task 3 - Write an else line that responds to anything else the user enters for your favourite food question. 4. Multiple elifs Despite what you did in task 3, programs can be expanded with more than one elif line. Underneath your first elif line but before your else line, add at least two more elif sections that respond differently depending on what is entered. Use the elif line from the task 2 picture to help you. Task 4 - Read the description above and use task 2 to help you. Challenge Programs Use everything that you have learned on this page to help you create these programs... Challenge Task 1 - Spanish Translation Create a new Python program. Save it as ' 5-Translator.py ' Add a comment at the top with your name and the date. Create a program that asks for a number between 1 and 4. Use if and elif statements to see what the user has entered and print a statement that displays the chosen number in Spanish - use the image to help you understand. BONUS : Add an else line for any numbers higher than 4. When you run it, it could look something like this: Challenge Task 2 - Able to Vote Create a new Python program. Save it as ' 5-Vote.py ' Add a comment at the top with your name and the date. Create a program that asks for their age. Use an if statement to see if the age is more than 17 (use > instead of ==). If the age is over 17, then print "You are old enough to vote!" Use an else statement to print a different message for everyone else. When you run it, it could look something like this: Challenge Task 3 - Totals Create a new Python program. Save it as ' 5-Totals.py ' Add a comment at the top with your name and the date. Use an int input line to ask the user for number 1. Use an int input line to a sk the user for number 2. Multiply the two numbers together and save it into a variable called total. If the total is over 9000, then print "It's over 9,000!!!" Use an else statement to print the total if it is less than 9000. When you run it, it could look something like this: <<< #4 Calculations #6 Turtle >>>

Learn how to spot a phishing email and other ways to stay secure online including choosing strong passwords. Scams & Staying Safe Part 1: Phishing Scams A phishing scam is when an attacker will send you an email pretending to be someone you trust . They are trying to get your username, password or other sensitive information . What does a phishing email look like? Capital letters and exclamation marks may be used to create a sense of urgency. A phishing email might be sent from a long, unrecognisable email address . It may be similar but slightly different to a real email address. An attacker might not know your name , so they will use your email address. A phishing email might contain spelling and grammar mistakes , so look carefully. Check any links carefully , if it looks suspicious, don't click it. Phishing emails try to rush you into making a silly decision. Don't panic and read the email carefully. Part 2: Secure webpages When you are browsing the web , you should stick to websites that you know and trust. Don't click on any links that you don't recognise , especially from strangers . How do i know a web page is secure? HTTP is a protocol (set of rules) for displaying a web page . If the web address at the top of your web browser starts with HTTP then it is not secure . Do not enter any personal information on an insecure web page. HTTPS is a protocol (set of rules) for displaying a secure web page. If you see a padlock in the address bar of your web browser then you know it is safer to enter information . Part 3: Strong passwords Your passwords must be secure so they cannot be broken easily. How to choose a strong password: ********* Passwords should be more than at least 8 characters long. Passwords should use numbers and punctuation marks . Aa Bb Cc Dd Ee Passwords should use uppercase and lowercase letters . You should use a different password for each account that you have. Passwords should not use words found in the dictionary . KS3 Home

Learn about ways to measure the success of protection. Based on the 2016 OCR Cambridge Technicals Level 3 IT specification for Unit 2 (Global Information). 6.4 - Protection Measures Exam Board: OCR Specification: 2016 - Unit 2 Staff Responsibilities It is the staff of an organisation that will spend the most time handling and amending data so the company must have sufficient and effective protection measures in place so that staff are confident in their role and know their responsibilities of information security. Certain staff members may be responsible for types of data within an organisation, such as personal and confidential data. Clearly assigning specific people to roles ensures that they know what their job is and that they are responsible if data is lost. Organisations also need to carefully consider which members of staff have access rights to certain information. If data is sensitive or confidential then the more people that have access to that data , the higher the risk of it being lost or tampered with (accidentally or on purpose). Sensitive data should only be handled and accessed by those who need to use it as part of their job role to limit the chance of data loss. Staff should be trained so that they know how to adequately handle information including basic data security techniques and how to protect data from unauthorised access and loss. Disaster & Recovery Planning With important data often stored on a computer network, it is absolutely vital that a detailed and effective disaster recovery policy is in place in the event of data being lost due to an unexpected disaster. Disasters include natural disasters (e.g. fire, flood, lightning), hardware failure (e.g. power supply unit failing), software failure (e.g. virus damage) and malicious damage (e.g. hacking). There are three clear parts to a disaster recovery policy: Before the disaster: All of the possible risks should be analysed to spot if there are any weaknesses in preparation. Preventative measures should be taken after the analysis, such as making rooms flood-proof or storing important data at a different location . Staff training should take place to inform employees what should happen in the event of a disaster. During the disaster: The staff response is very important – employees should follow their training and ensure that data is protected and appropriate measures are put in place. Contingency plans should be implemented while the disaster is taking place, such as uploading recent data to cloud storage or securing backups in a safe room and using alternative equipment until the disaster is over. After the disaster: Recovery measures should be followed, such as using backups to repopulate computer systems. Replacement hardware needs to be purchased for equipment that is corrupted or destroyed. Software needs to be reinstalled on the new hardware. Disaster recovery policies should also be updated and improved . Assessment and Effectiveness Organisations should conduct information security risk assessments periodically to ensure that their physical and logical measures are up-to-date and that they provide the most effective methods of protection. There may be training drills of what should happen if a disaster or substantial data loss occurs so that the company is prepared . By testing the security measures in place, they can identify any weak-points and fix those highlighted vulnerabilities to minimise the possibility of external and internal data intrusion. As part of an organisation's security assessment, they may identify specific cost impacts . These are necessary financial expenditures to ensure the security of data and systems, such as: Software - e.g. security software such as firewalls may be purchased to protect networked systems. Hardware - e.g. buying secure storage devices and new computer systems. Training - e.g. hiring industry experts to train staff on how to keep data secure. Security - e.g. hiring staff to protect server rooms. Q uesto's Q uestions 6.4 - Protection Measures: 1. Describe why staff are so important when it comes to data protection . [3 ] 2. Explain the steps an organisation should take as part of a disaster recovery plan . Split your answer into before, during and after the disaster. [12 ] 3. Why is it important to conduct information security risk assessments ? [2 ] 4. Describe two cost impacts to a bank of keeping customer data secure. [4 ] 6.3 - Impacts Topic List 6.5 - Physical Protection

Learn how to use logical operators in Python. Try practice tasks and learn through text and images. Perfect for students learning GCSE Computer Science in UK schools. top Python 4c - Logical Operators AND Operator The AND operator is used to execute certain code if more than one thing is true . AND is commonly used with account logins - both the username AND the password must be correct . The example below requires both a secret word and a secret number to be correct: print ( "To enter you need the secret word and the secret number!" ) word = input ( "What is the secret word? " ) number = int ( input ( "What is the secret number? " )) if word == "solitude" and number == 2011: print ( "Correct! You may enter!" ) else : print ( "Incorrect! Get out of here!" ) If no part or only some of the if statement is true then the indented code will not run : To enter you need the secret word and the secret number! What is the secret word? solitude What is the secret number? 4503 Incorrect! Get out of here! To enter you need the secret word and the secret number! What is the secret word? windhelm What is the secret number? 1021 Incorrect! Get out of here! Only If all parts of the if statement are true will the indented code be executed : To enter you need the secret word and the secret number! What is the secret word? solitude What is the secret number? 2011 Correct! You may enter! Logical Operators Task 1 ( Three Easy Questions) Ask the user three easy questions and print a special response if they get all three correct . Use the and operator to see if their answer for all each of the questions is correct. You must use a unique variable nam e for each of your inputs (it can't be 'answer' for all three, for example). Example solutions: What is the capital of Germany? Berlin What is the chemical formula for water? H20 What year did World War Two end? 1945 You absolute genius! What is the capital of Germany? Vienna What is the chemical formula for water? W20 What year did World War Two end? 1945 Bit awkward, I thought you'd do better... OR Operator The OR operator is used to execute certain code if one of several statements is true . The program below is checking if either a , e , i , o or u were entered. letter = input ( "Enter a letter: " ) if letter == "a" or letter == "e" or letter == "i" or letter == "o" or letter == "u" : print ( "You entered a vowel." ) else : print ( "You entered a consonant." ) Enter a letter: f You entered a consonant. Enter a letter: e You entered a vowel. It is important that you re-write the variable and operator (e.g. letter ==) each time you use 'or' . It will not work if you just write: if letter == “a” or “e” or “i” or “o” or “u”: Logical Operators Task 2 ( Twins?) Ask the user to enter their favourite colour and then ask them their age . If their favourite colour is the same as yours AND their age is the same as yours then print “Snap! Are you my twin?” . If only one of the statements is true (use the OR operator) then print “Spooky! You’re a bit like me.” . Add an else statement to print “We’re not so similar, you and I.” if there's nothing in common. Example solutions: What's your favourite colour? green What's your age? 15 Snap! Are you my twin? What's your favourite colour? blue What's your age? 15 Spooky! You're a bit like me. What's your favourite colour? red What's your age? 16 We're not so similar, you and I. ⬅ 4b - Mathematical Opera tors Sectio n 4 Practice Tasks ➡

Learn about the two types of language levels, high level and low level, including explanations and examples. Based on the 2020 Eduqas (WJEC) GCSE specification. 7.1: Language Levels Exam Board: Eduqas / WJEC Specification: 2020 + There are two types of programming languages used within computer systems: High-Level Languages Why do programmers use high-level languages? H igh-level programming languages use code written in a way that is similar to a natural human language , such as English, making it easier to understand and use the language. Using high-level languages leads to fewer errors and allows for more powerful and complex commands compared to low-level languages. However, a high-level language must be translated into machine code (binary) before it can be run, as high-level languages cannot be executed directly by the CPU . Popular high-level languages: PYT HON C++ Ja v a Visual Basic Low-Level Languages Low-level languages do not closely resemble a natural human language , making it harder for humans to understand and write in. Low-level languages are used when a program must be executed quickly or when programmers need to write code that interacts directly with the hardware , such as device drivers. There are two types of low-level language : Machine Code This is the pure binary code that computers can directly process and execute . It is extremely tedious and difficult for humans to understand and write machine code. However, machine code can be used when a programmer needs to perform a very specific command that can't be done in a high-level language. Machine code will be executed faster than high-level programs because it is already in a format the CPU can execute and does not need to be translated . 0010 1011 0101 0101 0110 0111 0101 0001 0101 0101 0101 0100 1010 1010 1010 1010 1111 1110 0010 1001 0100 1001 0010 0111 0111 0101 0011 1010 1000 0101 0110 0111 0000 1010 1010 0011 1101 1001 0010 1101 0010 0100 1001 0011 1010 1001 0101 0101 0010 0101 0111 0101 0101 1000 1011 0111 Assembly Language Assembly language uses specialised command mnemonics to perform actions . See the Assembly Language section in the programming tab for a list of mnemonics such as INP , OUT and HLT . Assembly language is preferred by many programmers over machine code because it is easier to understand and spot errors . It is faster to execute than high-level languages and, like machine code, can be used to directly control the CPU . Q uesto's Q uestions 7.1 - Language Levels: 1a. Describe three reasons why programmers use high-level languages . [ 3 ] 1b. Explain one limitation of using high-level languages . [2 ] 2a. Describe a key difference between low-level languages and high-level languages . [ 2 ] 2b. Describe when a low-level language would be used instead of a high-level language . [2 ] 2c. Describe an advantage and a disadvantage of writing directly in machine code . [2 ] 2d. Describe what assembly language is. Give one benefit to using assembly language instead of machine code and one benefit to using it instead of a high-level language . [3 ] 3. Compare high-level and low-level languages by stating which is: a. Easier to understand [ 1 ] b. Requiring translation [ 1 ] c. Quicker to execute [ 1 ] INP STA Number1 OUT HLT Number1 DAT 6.2 - Utility Software Theory Topics 8.1 - Programming Principles

Learn about malware such as viruses, worms, trojans, spyware, keyloggers and ransomware. Also, learn about phishing, data theft, interception and cyber attacks including SQL injection, IP address spoofing, DDoS attacks and brute force. Based on the 2020 Eduqas (WJEC) GCSE specification. 3.8: Cyber Threats Exam Board: Eduqas / WJEC Specification: 2020 + 3.8a: Malware What is malware? Malware is any type of harmful program that seeks to damage or gain unauthorised access to your computer system. Virus A virus can replicate itself and spread from system to system by attaching itself to infected files . A virus is only activated when opened by a human . Once activated, a virus can change data or corrupt a system so that it stops working . Worm A worm can replicate itself and spread from system to system by finding weaknesses in software . A worm does not need an infected file or human interaction to spread. A worm can spread very quickly across a network once it has infiltrated it. Trojan A trojan is a harmful program that looks like legitimate software so users are tricked into installing it . A trojan secretly gives the attacker backdoor access to the system . Trojans do not self replicate or infect other files. Spyware Spyware secretly records the activities of a user on a computer. The main aim of spyware is to record usernames, passwords and credit card information . All recorded information is secretly passed back to the attacker to use. Keylogger A keylogger secretly records the key presses of a user on a computer. Data is stored or sent back to the attacker. The main aim of a keylogger is to record usernames, passwords and credit card information . Keyloggers can be downloaded or plugged into the USB port . Ransomware Ransomware locks files on a computer system using encryption so that a user can no longer access them. The attacker demands money from the victim to decrypt (unlock) the data . ? ? ? ? Attackers usually use digital currencies like bitcoin which makes it hard to trace them. 3.8b: Data Theft Phishing Phishing is the method of misleading individuals or organisations into sharing sensitive information (such as passwords or bank details ), often through the use of emails . Phishers may pose as a trusted company like Amazon or YouTube to direct users to open malicious attachments or encourage them to follow fraudulent links to steal their data . Social Engineering Social engineering means to trick others into revealing their personal data by posing as a trusted source . For example, impersonating an IT technician of a school via email and asking for a student's username and password . Interception This is when data packets on a network are intercepted by a third party (e.g. a hacker) and copied to a different location than the intended destination. Software called packet sniffers are used to intercept and analyse data packets. Physical Theft Computer systems (e.g. laptops) or storage devices (e.g. USB stick) may be stolen in public or from offices. Unwanted systems and storage media should be disposed of securely as data could be stolen from discarded information , such as old CDs or even printed paper. 3.8c: Online Threats & Attacks Hacking Hacking is the method of exploiting weaknesses in a system or network to create, view, modify or delete files without permission. A hacker is anyone who gains access to data or systems that they do not have authority to access. DoS Attack A DoS (Denial of Service ) attack is when a computer repeatedly sends requests to a server to overload the system . A server overload will slow the system and may take websites offline temporarily. A DDoS (Distributed Denial of Service ) attack is a coordinated attack using a botnet of infected systems to overload a server with requests . A botnet is a large group of devices controlled and used maliciously by an attacker. SQL Injection SQL ( Structured Query Language ) is a programming language used for manipulating data in databases . A SQL injection is when a malicious SQL query (command) is entered into a data input box on a website. If the website is insecure then the SQL query can trick the website into giving unauthorised access to the website’s database . An SQL injection can be used to view and edit the contents of a database or even gain administrator privileges . ' or 1 = 1 Brute Force Attack In order to break a password , every possible combination is tested in order from start to finish . This is not a quick method but it should break the password eventually and can be sped up if multiple computer systems are used at the same time. IP Address Spoofing An attacker changes the IP address of a legitimate host so any visitors to the URL are instead taken to a spoofed ( fake ) web page . This web page is used to record any inputted data (such as usernames and passwords) and send it back to the attacker . The spoofed web page can also be used to install malware . Q uesto's Q uestions 3.8 - Cyber Threats: 3.8a - Malware: 1. What is malware ? [ 2 ] 2a. Describe three characteristics of a virus . [3 ] 2b. Describe three characteristics of a worm . [3 ] 2c. What is a trojan ? [ 3 ] 2d. Describe how spyware and keyloggers work. [ 4 ] 2e. Explain how ransomware works and why it is difficult to trace attackers . [ 3 ] 2f. In your opinion, which malware do you think is the most dangerous and why ? [ 2 ] 3.8b - Data Theft: 1. Describe what is meant by ' phishing ' . [ 2 ] 2. Give an example of social engineering . [ 2 ] 3. What is interception ? What software is used to intercept data packets? [ 2 ] 4. Describe why systems and storage media should be disposed of securely . [ 1 ] 3.8c - Online Threats & Attacks: 1. Describe what is meant by ' hacking ' . [ 2 ] 2a. Describe what a DoS attack is and its impact . [2 ] 2b. Describe how a DDoS attack is different to a DoS attack . [2 ] 3. Describe what an SQL injection is and how an attacker would use it. [ 4 ] 4. Describe what is meant by a brute force attack . [ 2 ] 5. Describe IP address spoofing and its purpose . [ 3 ] 3.7 - The Internet Theory Topics 3.9 - Protection Against Threats

Learn about the three logical operators - NOT, AND and OR - as well as truth tables. Based on the J277 OCR GCSE Computer Science specification (first taught from 2020 onwards). 4.1: Boolean Logic Exam Board: OCR Specification: J277 Watch on YouTube : Boolean Operators & Truth Tables Logic Gate Diagrams What is a logical operator? Inside of each computer system are millions of transistors . These are tiny switches that can either be turned on (represented in binary by the number 1 ) or turned off (represented by 0 ). Logical operators are symbols used to represent circuits of transistors within a computer. The three most common operators are: NOT AND OR What is a truth table? Truth tables are used to show all possible inputs and the associated output for each input . The input and output values in a truth table must be a Boolean value - usually 0 or 1 but occasionally True or False. NOT AND OR A NOT logical operator will produce an output which is the opposite of the input . NOT is also known as Negation . The symbol for NOT is ¬ An AND logical operator will output 1 only if both inputs are also 1 . AND is also known as Conjunction . The symbol for AND is ∧ An OR logical operator will output 1 if either input is 1 . OR is also known as Disjunction . The symbol for OR is ∨ NOT Logic Gate AND Logic Gate Symbol OR Logic Gate Symbol Truth Table Truth Table Truth Table Multiple Operators Exam questions could ask you complete truth tables that use more than one logical operator . Work out each column in turn from left to right and look carefully at which preceding column you need to use. NOT B A AND NOT B A OR (A AND NOT B) As binary is a base-2 number system , the number of rows required in a truth table will double with each new input in the expression in order to show the unique combinations of inputs. The examples above use just two inputs (A + B) so 4 rows are required. e.g. A = 2 rows / A + B = 4 rows / A, B + C = 8 rows / A, B, C + D = 16 rows Logic Diagrams You may be asked in an exam to d raw a logic diagram when given a logical expression . Draw any NOT symbols or expressions in brackets first. A logic diagram for C = ¬A ∧ B A logic diagram for D = C ∨ (A ∧ B) Q uesto's Q uestions 4.1 - Boolean Logic: 1. Copy and complete the following truth tables: 1b. Simplify the expression in the second truth table. 2a. A cinema uses a computer system to monitor how many seats have been allocated for upcoming movies. If both the premium seats and the standard seats are sold out then the system will display a message. State the type of logical operator in this example. 2b. For the more popular movies, the cinema's computer system will also display a message if either the premium seats or the standard seats have exclusively been sold out. However, it will not output a message when both have been sold out. State the type of logical operator in this example. 3. Draw a logic diagram for C = (¬B v A) ∧ A . 3.2 - Testing Theory Topics 5.1 - Languages & Translators

A glossary of important code to be used in Greenfoot, such as random movement, using a counter removing objects and sound. Aimed at the Eduqas / WJEC GCSE specification. Greenfoot Code Glossary Greenfoot Home This code will work for Version 2.4.2 which is used in Component 2 of the 2016 WJEC/Edquas specification . Key Down 270 if (Greenfoot.isKeyDown("right" )) { setRotation(0); move(1); } 180 90 0 Bounce At Edge if (isAtEdge()) { turn(180); } move(1); if (Greenfoot.getRandomNumber(10)<1) { turn(Greenfoot.getRandomNumber(90) - 45); } Random Remove Object if (isTouching(Apple.class )) { removeTouching(Apple.class ); } Play Sound Greenfoot.playSound("pop.wav" ); Stop Greenfoot.stop(); Counter - (Write this code when an object is removed) Counter counter = (Counter) getWorld().getObjects(Counter.class ).get(0); counter.add(1); Stuck? If you start typing but can't remember what commands come next, press Ctrl and Space together to show a list of all possible commands that you can use.

Learn about the differences between wired and wireless networks. Based on the J277 OCR GCSE Computer Science specification (first taught from 2020 onwards). 3.2a: Wired & Wireless Networks Exam Board: OCR Specification: J277 Watch on YouTube : Wired Networks Wireless Networks Encryption Wired Connections Wireless Connections Wireless connections, such as WiFi or Bluetooth , use no cables but require a wireless network interface card (WNIC ). Wireless connections generally have a slower speed and can be affected by the computer's distance from the wireless router as well as obstacles like walls or bad weather. Wired connections use physical cables , such as copper or fibre optic wires , and require a network interface card (NIC ) to connect to a network. These wired connections use a wired connection protocol - most commonly Ethernet . Restricted Movement Faster More Secure NIC Required Freedom of Movement Slower Less Secure WNIC Required Encryption Wireless connections are less secure and require encryption . Encryption is the process of scrambling data into an unreadable format so that attackers cannot understand it if intercepted during transmission. The original data (known as plaintext ) is converted to scrambled ciphertext using an encryption key . Only at the correct destination will the encryption key be used to convert the ciphertext back into plaintext to be understood by the receiving computer. Q uesto's Q uestions 3.2a - Wired & Wireless Networks: 1. Briefly compare wired and wireless networks in terms of movement , transmission speed , security and required hardware . You could answer this in the form of a table. [ 8 ] 3.1b - Network Hardware & Internet Theory Topics 3.2b - Protocols & Layers

Learn about how to convert between the denary (decimal), binary and hexadecimal number systems. Based on the J277 OCR GCSE Computer Science specification (first taught from 2020 onwards). Exam Board: OCR 2.4a: Number Systems Specification: J277 Watch on YouTube : Binary and Denary Hexadecimal Number System Ranges Binary to Denary Denary to Binary Binary to Hexadecimal Hexadecimal to Binary Denary to Hexadecimal Hexadecimal to Denary What is binary? By now you should know that computer systems process data and communicate entirely in binary . Topic 2.3 explained different binary storage units such as bits (a single 0 or 1), nibbles (4 bits) and bytes (8 bits). Binary is a base 2 number system. This means that it only has 2 possible values - 0 or 1 . What is denary? Denary (also known as decimal ) is the number system that you've been using since primary school. Denary is a base 10 number system. This means that it has 10 possible values - 0, 1, 2, 3, 4, 5, 6, 7, 8, and 9 . Binary & Denary Convert from binary to denary: Convert from denary to binary: Hexadecimal What is hexadecimal? Hexadecimal is a base 16 number system. This means that it has 16 possible values - 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, A, B, C, D, E and F . Hexadecimal is used as a shorthand for binary because it uses fewer characters to write the same value . This makes hexadecimal less prone to errors when reading or writing it , compared to binary. For example, 100111101011 in binary is 9EB in hexadecimal. Hexadecimal only uses single-character values. Double-digit numbers are converted into letters - use the table on the right to help you understand. Binary to hexadecimal: Hexadecimal to binary: Converting from denary to hexadecimal / hexadecimal to denary To convert from denary to hexadecimal or from hexadecimal to denary , it is easiest to convert to binary first . However, it is possible to convert directly from denary to hexadecimal or directly from hexadecimal to denary . The videos below explain both methods . Denary to hexadecimal: Hexadecimal to denary: Watch on YouTube Watch on YouTube Watch on YouTube Watch on YouTube Watch on YouTube Watch on YouTube Q uesto's Q uestions 2.4a - Number Systems: 1. Explain why hexadecimal numbers are used as an alternative to binary . Use an example . [ 3 ] 2. Convert the following values from binary to denary : a. 00101010 b. 11011011 c. 01011101 d. 11101110 e. 01011111 [1 each ] 3. Convert the following values from denary to binary : a. 35 b. 79 c. 101 d. 203 e. 250 [1 each ] 4. Convert the following values from binary to hexadecimal : a. 11110101 b. 01100111 c. 10111010 d. 10010000 e. 11101001 [1 each ] 5. Convert the following values from hexadecimal to binary : a. C2 b. 8A c. DE d. 54 e. F7 [1 each ] 6. Convert the following values from denary to hexadecimal : a. 134 b. 201 c. 57 d. 224 e. 101 [1 each ] 7. Convert the following values from hexadecimal to denary : a. 32 b. A5 c. 88 d. C0 e. BE [1 each ] Click the banners below to try self-marking quizzes (Google Forms) on these topics. Binary to Denary: Denary to Binary: Binary to Hexadecimal: Hexadecimal to Binary: 2.3 - Data Units Theory Topics 2.4b - Binary Addition & Shifts

App Inventor Task 1 & 2 - Basic Apps Basic Program #1 - Colour Changer This quick tutorial will teach you how to create an app that changes the background colour when you press different buttons . See the video: In Designer layout, firstly drag four buttons from the Palette tab on the left side and drop them one at a time on top of each other in the Viewer . In the Components tab, click on each button and press Rename to change the name (this makes it easier to code them later). You don't need to choose these four colours, but it is a good idea to start with these (you can change them later). You should notice that you are only changing the name of the button - not the button on the text; these are two different variables . Now to change the text on each button. Click on a button in the centre then in the Properties tab on the right scroll down to Text and change the text to a colour. When you've changed all four button texts, then you can start to code. Click on the Blocks button in the top right to start adding the code. In the Blocks tab on the left click on each button block (e.g. Red, Blue, Green and Yellow) and drag over a 'when click ' block for each colour. Blocks we put inside of the 'when click' blocks will execute whenever that button is pressed. Grab a set Screen 1 BackgroundColor from the Screen1 section in the Blocks tab and place one underneath each when click block. Then line up the correct colour from the Colors section in the Blocks tab to the relevant button. Program 1 Complete! The easiest way to run an app that you have created at home using App Inventor 2 is to download the free MIT AI2 Companion App on your smartphone from the Google Play Store . At the top of the App inventor program on your computer , click on Connect and AI Companion . This will generate a six-digit code you can type into your phone. If your school has the emulator installed, you can also use this to test your app. Ideas to Improve Your App: Use the when Screen1 BackPressed block from the Screen1 section in Blocks to turn the background colour white when the back button is pressed. The block is shown to the right; you can work out how to use it. Add more buttons for different colours. Try purple, black and orange for example. Change the BackgroundColour (in Properties ) of each button to represent the colour it says. You might need to change the TextColour too for red and blue (see the image to the right). Password Checker Basic Program #2 - Password Checker This quick tutorial will teach you how to create an app that requires a user to enter a correct password . See the video - maximise to see it clearly: Firstly you need to grab a TextBox from the Palette tab on the left and place it in the Viewer. Then drag a Button and a Label . Put them in this order: You need to change the Text for the button in the Properties tab to 'Enter Password'. Click on your text box and delete the Hint Text from the Properties tab. Click on the label and delete the Text from the Properties tab. Don't worry, the label is still there! Now time to code. Open up the Blocks layout by clicking Blocks in the top right. Drag a when Button1 click block into the centre from the Button1 section in Blocks . Drag an if then block from Control within the when Button 1 click block. Click on the blue cog button and, in the new window underneath, drag an else block within the if block. The top part will update by itself. When the button is clicked we want to see if the text in the text box matches what we want it to be. Grab an = block from Logic and connect it to the if block. Then place a TextBox1 Text block from TextBox1 in the first half and a blank " " block from Text in the second half. In the " " block write what you want the password to be. I've chosen pikachu because pikachu is cool. Grab a Set Label1 Text block from Label1 and put one next to then and another next to else. Place a " " block from Text and snap it next to both of those blocks. If the user has entered the password correctly then you want 'Correct Password' to appear. Otherwise, if they have entered anything else , you want 'Incorrect Password' to appear. Program 2 Complete! The easiest way to run an app that you have created at home using App Inventor 2 is to download the free MIT AI2 Companion App on your smartphone from the Google Play Store . At the top of the App inventor program on your computer , click on Connect and AI Companion . This will generate a six-digit code you can type into your phone. If your school has the emulator installed, you can also use this to test your app. Ideas to Improve Your App: Change the password to something different. If the correct password is entered change the background to gree n . If an incorrect password is entered change the background to red . You may want to scroll up to the first program as a reminder. KS3 Home Task 3

Learn about each of the 8 stages of data analysis including exactly what should occur at every stage. Based on the 2016 OCR Cambridge Technicals Level 3 IT specification for Unit 2 (Global Information). 3.4 - Stages of Data Analysis Exam Board: OCR Specification: 2016 - Unit 2 Data analysis is the process of identifying and collecting data to be viewed and modelled, in the aim of discovering patterns or trends that can be used for conclusions and decision-making. 1. Identify the need Before anything else can take place, objectives are set for what the data analysis will hope to achieve. Aims must be clear and well defined . For example, an organisation should define what information will be needed and what exactly they want to find out by the end of the process (the purpose of the data analysis). Not clearly defining the required information or purpose could lead to worthless results and a waste of the entire data analysis process. 2. Define the scope In this stage the restrictions of the project are defined. Scope includes factors such as budget , content , detail , timescales (deadlines) and any further constraints . 3. Identify potential sources Project planners must identify a wide range of sources for the potential information, ensuring that it is unbiased and covers the objectives . The specific data will depend on the project but it could include sales figures or customer surveys for example. 4. Source and select information Information is gathered from the identified sources in stage three. Any unsuitable data is excluded so that results are not unreliable as poor quality information can lead to numerous negative consequences . Planners will have to determine the accuracy and reliability of any identified sources and select the best . 5. Select the most appropriate tools There are many different data analysis tools that can be used as part of this sequence; in this stage the most appropriate tool for the project is selected. Examples include methods of presentation such as charts and graphs for a visual representation of data . Regression analysis can also be used - regression is the determining of relationships e.g. if the amount spent on advertising bottled water increases, will consumption increase too or are other factors involved? If there is a link, a business can continue to spend more on advertising if consumption and profit also rises. Trend analysis is another option - this shows patterns over time , for example, bottled water consumption each year over the past decade. 6. Process and analyse data Data has now been collected and can be inputted into software such as spreadsheets or databases to further analyse. Putting collected data into a spreadsheet for example allows for analysis to begin as graphs can be created from the data and any patterns or trends discovered. 7. Record and store information The data has been collected and analysed and now any findings are written into a report . Any patterns, trends or findings can be described with statistical evidence generated from the analysis. 8. Share results A report is worthless if not shared with the stakeholders . Sharing can take different forms such as a typed document posted out to stakeholders, an email with major findings summarised or as a post on a website . Q uesto's Q uestions 3.4 - Stages of Data Analysis: 1. List the 8 stages of data analysis in order. [8 ] 2. A supermarket chain called 'Fresh Food UK' wants to complete data analysis to see which stores across the country have been most profitable in the last year . Explain how Fresh Food UK would use each of the 8 stages of data analysis . [16 ] 3.2 & 3.3 - Information Categories Topic List 3.5 - Data Analysis Tools