ACTIVITIES:

LESSON RESOURCES:

• HEDYCODE

What Do We Know About Computers?

Computers are amazing machines that help us do many things, like playing games, writing stories, and finding information.

What is a Computer?

A computer is an electronic device that can store, process, and display information. We discussed in class what is and what is not a computer using examples/

What is Not a Computer?

Actually, many devices we use every day, like microwaves and washing machines, are also computers. They are called embedded systems because they focus on a limited set of tasks. These devices can take input (like pressing buttons), process data (like a timer), and give output (like heating, pumping water).

Input and Output Devices

Input devices are tools we use to give information to a computer. Examples include:

• Mouse: Helps us move the cursor and click on things.

• Keyboard: Allows us to type letters and numbers.

• Dial: To set a washing cycle.

Output devices are tools that show us the results of the computer's work. Examples include:

• Monitor: Displays images and text.

• Printer: Produces a physical copy of documents.

• Pump: To pump water into the drum of a washing machine.

Electricity and Binary

Electricity is the power that makes computers work. Inside a computer, electricity flows through tiny pathways called circuits.

Binary is the language in which we talk about electricity flowing through the circuits a '1' for more than 5V and 0 for less/equal to 5V. We decided to call these two states 0 and 1. However, 0 and 1 don't really exist as numbers inside the computer. Instead, the computer understands electricity. The chips inside a computer are made up of tiny switches that change state with the amount of voltage they receive. When the switch is on, it represents a 1, and when it's off, it represents a 0.

High-Level and Low-Level Programming Languages

Programming languages are the tools we use to give instructions to a computer. There are two main types:

1. High-Level Programming Languages: These are easier for humans to understand. They use words and symbols that are similar to our everyday language. Examples include Python and Java. Think of them as the friendly languages that make it easier to talk to computers. They are slower to run because they need to be translated more before being at the binary level.

2. Low-Level Programming Languages: These are closer to the computer's binary language. They are harder for humans to understand but give more control over what the computer does. Examples include Assembly and Machine Code. Think of them as the detailed instructions that tell the computer exactly what to do. They run faster, because they are closer to binary.

Embedded Systems vs. General-Purpose Computers

An embedded system is a computer designed to do one specific task. For example, a microwave's computer controls cooking, and a washing machine's computer controls washing cycles.

A general-purpose computer, like a PC (personal computer), can perform many different tasks. You can use it to write documents, browse the internet, play games, and much more.

Moore's Law

Moore's Law is the observation that the number of transistors on a computer chip doubles approximately every two years. This means computers get faster and more powerful over time.

ASCII and Unicode

ASCII (American Standard Code for Information Interchange) is a way to represent text using numbers. Each letter, number, and symbol is assigned a unique number. For example, the letter 'A' is represented by the number 65.

Unicode is a more advanced system that includes many more characters from different languages and symbols. It allows computers to represent text from all over the world.

How Colors are Represented

Colors on a computer screen are made up of tiny dots called pixels. Each pixel can show different colors by mixing three basic colors: Red, Green, and Blue (RGB). By changing the intensity of these colors, we can create millions of different colors.

Color Depth refers to the number of bits used to represent the color of a single pixel. More bits mean more colors. For example:

• 8-bit color can show 256 colors.

• 24-bit color can show over 16 million colors.

Analog to Digital Conversion

Many things in the real world, like sound and light, are analog. This means they have continuous values. Computers, however, work with digital data, which has discrete values (like 0s and 1s).

Analog to Digital Conversion is the process of turning continuous analog signals into digital data that a computer can understand. For example, when you record your voice, the microphone captures the sound waves (analog) and converts them into digital data that the computer can store and process.

How Sound is Represented

Sound is represented in computers by converting sound waves into digital data. This process is called sampling. The sampling rate is the number of samples taken per second. Higher sampling rates mean better sound quality.

Compression

Compression is a way to reduce the size of files so they take up less space on a computer. There are two types:

• Lossless Compression: No data is lost, and the original file can be perfectly restored.

• Lossy Compression: Some data is lost, but the file size is much smaller. This is often used for images and videos.

Programming Languages

Programming languages are tools we use to give instructions to a computer. Here are a few examples:

• Assembly Language: A low-level language that is very close to the computer's binary code. It gives detailed control over the computer's hardware.

• C++: A high-level language that is powerful and used for many applications, like games and software development.

• Python: A high-level language that is easy to read and write. It's great for beginners and is used in web development, data analysis, and more.

What is Pseudocode?

Pseudocode is a way to plan out a program using plain language. It helps programmers think through their code before writing it in a programming language. It's like writing a recipe for a computer to follow.

What is Cyber Security?

Cyber security is all about keeping our computers, tablets, smartphones, and other devices safe from bad people who want to steal information or cause problems. Think of it like locking the doors and windows of your house to keep burglars out.

Common Cyber Security Threats

1. Malware:

   • What is it?: Malware is like a computer virus that can make your device sick.

   • Types of Malware:

     • Viruses: These attach themselves to other programs and spread when you use those programs. They can delete files or make your computer slow.

     • Worms: These spread on their own without needing you to do anything. They can make lots of copies of themselves and use up your computer's resources.

     • Trojans: These pretend to be useful programs, but once you install them, they can do bad things like stealing your information.

     • Ransomware: This locks your files and asks for money to unlock them.

     • Spyware: This secretly watches what you do on your computer and sends the information to someone else.

     • Adware: This shows you unwanted ads and can also track what you do online.

2. Phishing:

   • What is it?: Phishing is when someone tries to trick you into giving them your personal information, like passwords or credit card numbers.

   • How it works: They might send you fake emails that look like they’re from a trusted company, asking you to click on a link or open an attachment.

3. Pharming:

   • What is it?: Pharming is when someone tricks your computer into going to a fake website that looks real.

   • How it works: They change the settings on your computer or the internet to redirect you to a fake website where you might enter your personal information.

4. Social Engineering:

   • What is it?: Social engineering is when someone tricks you into giving them information or doing something for them.

   • How it works: They might pretend to be someone you trust, like a friend or a company employee, to get you to share your personal information.

5. DDoS Attacks:

   • What is it?: DDoS (Distributed Denial of Service) attacks flood a website with so much traffic that it crashes and can’t be used.

   • What it does: It makes websites slow or unavailable.

Differences Between Viruses, Worms, and Trojans

• Viruses:

  • How they spread: Attach themselves to other programs and need you to run those programs to spread.

  • Impact: Can delete files, make your computer slow, or cause other problems.

• Worms:

  • How they spread: Spread on their own without needing you to do anything.

  • Impact: Can make lots of copies of themselves and use up your computer's resources.

• Trojans:

  • How they spread: Pretend to be useful programs to trick you into installing them.

  • Impact: Can steal your information or cause other problems once installed.

https://www.youtube.com/watch?v=2xdV-xut7EQ 

1. Use Strong Passwords:

   • What is it?: A strong password is one that is difficult for others to guess. It should be a mix of letters (both uppercase and lowercase), numbers, and symbols.

   • Why it’s important: Strong passwords make it harder for hackers to access your accounts.

   • How to do it:

     • Avoid using easily guessable information like your name, birthdate, or the word "password."

     • Use a combination of uppercase letters, lowercase letters, numbers, and symbols.

     • Make your password at least 12 characters long.

     • Example: Instead of using "password123," use something like "P@ssw0rd!23".

2. Don’t Share Personal Information:

   • What is it?: Be cautious about sharing your personal details online, such as your full name, address, phone number, or school name.

   • Why it’s important: Sharing too much information can make it easier for bad people to steal your identity or find out more about you.

   • How to do it:

     • Only share personal information on trusted websites.

     • Be careful about what you post on social media. Avoid posting your location or other sensitive details.

     • Use privacy settings to control who can see your information.

3. Be Careful with Emails and Links:

   • What is it?: Don’t click on links or open attachments in emails from people you don’t know.

   • Why it’s important: These could be phishing attempts or contain malware.

   • How to do it:

     • If you receive an email from someone you don’t know, don’t open any attachments or click on any links.

     • Look for signs of phishing, such as poor spelling and grammar, or a sense of urgency.

     • Verify the sender’s email address. If it looks suspicious, don’t interact with the email.

4. Keep Your Software Updated:

   • What is it?: Make sure your computer, tablet, or smartphone has the latest updates.

   • Why it’s important: Updates often fix security problems that could be exploited by hackers.

   • How to do it:

     • Enable automatic updates for your operating system and apps.

     • Regularly check for updates and install them as soon as they are available.

     • Use reputable software and avoid downloading apps from unknown sources.

5. Use Anti-Malware Software:

   • What is it?: Anti-malware software helps protect your device from viruses and other malicious software.

   • Why it’s important: It can detect and remove malware before it causes damage.

   • How to do it:

     • Install anti-malware software on your devices.

     • Keep the software updated to ensure it can protect against the latest threats.

     • Run regular scans to check for malware.

6. Enable Two-Factor Authentication (2FA):

   • What is it?: 2FA adds an extra layer of security by requiring two forms of identification to log in, like a password and a code sent to your phone.

   • Why it’s important: It makes it harder for hackers to access your accounts, even if they have your password.

   • How to do it:

     • Enable 2FA on your important accounts, such as email, social media, and banking.

     • Follow the instructions provided by the service to set up 2FA.

     • Use an authentication app or receive codes via SMS.

7. Be Wary of Public Wi-Fi:

   • What is it?: Public Wi-Fi networks, like those in cafes or airports, are less secure than private networks.

   • Why it’s important: Hackers can intercept data sent over public Wi-Fi.

   • How to do it:

     • Avoid accessing sensitive information, like online banking, over public Wi-Fi.

     • Use a Virtual Private Network (VPN) to encrypt your internet connection when using public Wi-Fi.

     • Turn off automatic connection to public Wi-Fi networks on your devices.

8. Back Up Your Data:

   • What is it?: Regularly save copies of your important files to another location.

   • Why it’s important: If your device is compromised, you won’t lose your important data.

   • How to do it:

     • Use an external hard drive or cloud storage service to back up your files.

     • Set up automatic backups to ensure your data is regularly saved.

     • Keep multiple copies of important files in different locations.

9. Educate Yourself and Others:

   • What is it?: Learn about the latest cyber security threats and how to protect yourself.

   • Why it’s important: Staying informed helps you recognize and avoid potential threats.

   • How to do it:

     • Read articles and watch videos about cyber security.

     • Share what you learn with friends and family to help them stay safe.

     • Participate in cyber security awareness programs at school or in your community.