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Internet

The Internet is a global network of interconnected computers and devices that communicate using standardized protocols.

It allows users to access and share information across the world. Here is a brief overview of how the Internet works, the types of protocols involved, coding languages and the hardware involved.

How the Internet Works

The Internet works by using a technique called packet switching, which involves breaking up data into small segments called packets and sending them over different routes to the destination.

Each packet contains both the data and information about the data, such as the source and destination addresses, the sequence number, and the error detection code.

The packets are routed by devices called routers, which forward them to the best available path based on various factors, such as traffic, congestion, and availability.

The routers use protocols such as IP (Internet Protocol) to identify and locate the devices on the network, and TCP (Transmission Control Protocol) to ensure reliable and ordered delivery of the packets.

At the destination, the packets are reassembled into the original data by the receiving device.

Types of Protocols

Protocols are the rules and standards that govern the communication and exchange of data over the Internet. There are many different types of protocols, each serving a specific purpose and function.

HTTP (Hypertext Transfer Protocol):This protocol is used to transfer hypertext documents, such as web pages, between web servers and web browsers. It defines the format and structure of the requests and responses, as well as the methods and status codes. For example, when you type a URL in your browser, you are sending an HTTP request to the web server, which responds with an HTTP response containing the web page content.

HTTPS (Hypertext Transfer Protocol Secure):This protocol is a secure version of HTTP, which encrypts the data using SSL (Secure Sockets Layer) or TLS (Transport Layer Security) protocols. This ensures that the data is protected from eavesdropping, tampering, and spoofing by third parties. For example, when you visit a website that has a padlock icon in the address bar, you are using HTTPS protocol.

FTP (File Transfer Protocol):This protocol is used to transfer files between computers on a network. It works on a client-server model, where the client initiates a connection to the server and requests a file, and the server sends the file to the client. FTP can also be used to upload files to a server, as well as to manage files and directories on a server. For example, when you download a file from a website, you are using FTP protocol.

SMTP (Simple Mail Transfer Protocol):This protocol is used to send and receive email messages over the Internet. It works on a store-and-forward model, where the sender’s mail server sends the message to the recipient’s mail server, which stores it until the recipient retrieves it. SMTP also defines the format and structure of the email messages, as well as the commands and responses. For example, when you send an email to someone, you are using SMTP protocol.

DNS (Domain Name System):This protocol is used to translate domain names, such as www.example.com, into IP addresses, such as 192.168.1.1, that computers can understand and locate. It works on a hierarchical and distributed database system, where each domain name is mapped to an IP address by a DNS server. DNS also provides other services, such as aliasing, caching, and load balancing. For example, when you enter a domain name in your browser, you are using DNS protocol to find the corresponding IP address.

Coding Languages

Coding languages are the languages that programmers use to write instructions for computers to perform specific tasks.

HTML (Hypertext Markup Language):This language is used to create the structure and content of web pages, such as headings, paragraphs, images, links, and forms. It uses tags and attributes to define the elements and properties of the web page. For example,

<p>Hello, world!</p> is an HTML code that creates a paragraph with the text “Hello, world!”.

CSS (Cascading Style Sheets):This language is used to style and format the appearance of web pages, such as colors, fonts, layouts, and animations. It uses selectors and rules to apply styles to the HTML elements. For example, p {color: blue;} is a CSS code that makes all the paragraphs blue.

JavaScript:This language is used to add interactivity and functionality to web pages, such as buttons, menus, forms, and games. It uses variables, functions, objects, and events to manipulate the HTML and CSS elements. For example, alert(“Hello, world!”); is a JavaScript code that displays a pop-up message with the text “Hello, world!”

PHP:This is a server-side scripting language that is widely used for web development and creating dynamic web pages. It can process data from web forms, interact with databases, generate HTML output, and perform various tasks on the web server

SQL:This is the standard language for managing and querying data in relational database systems, such as MySQL, Oracle, and PostgreSQL. It can create, modify, and delete tables, columns, rows, and indexes, and perform various operations on the data, such as selecting, inserting, updating, and deleting

Python:This is a high-level, general-purpose programming language that is popular for web development, data analysis, machine learning, and automation. It can be used for both server-side and client-side scripting, and it has a large and diverse library of modules and frameworks that support various web applications

Java:This is a compiled, object-oriented programming language that is designed to run on any platform that supports the Java Virtual Machine. It is widely used for web development, especially for creating large-scale, distributed, and enterprise-level applications. It can also create applets that run on web browsers, and Android applications that run on mobile devices

C:This is a low-level, compiled programming language that is one of the oldest and most influential languages in computer science. It is used to create operating systems, such as Unix and Linux, and various software applications, such as web browsers, web servers, and embedded systems. It is also the basis for many other programming languages, such as C++, C#, and Objective-C

C++:This is an extension of C that adds object-oriented and generic programming features, such as classes, inheritance, polymorphism, and templates. It is used for developing complex and high-performance applications, such as web browsers, game engines, graphics software, and scientific computing

C#:This is a modern, compiled, object-oriented programming language that is developed by Microsoft and runs on the .NET Framework. It is used for creating web applications, desktop applications, mobile applications, and games, using various technologies, such as ASP.NET, Windows Forms, Xamarin, and Unity

Ruby:This is a high-level, interpreted, general-purpose programming language that is known for its expressive and elegant syntax. It is used for web development, especially with the Ruby on Rails framework, which provides a fast and easy way to create dynamic and database-driven web applications

Rust:This is a relatively new, compiled, multi-paradigm programming language that focuses on performance, reliability, and concurrency. It is used for creating fast and secure web applications, such as web servers, web browsers, and web frameworks. It can also interface with other languages, such as C and JavaScript

How you can protect yourself on the web

• Don’t share personal information. This includes your full name, address, phone number, social security number, bank account details, and passwords. Hackers, scammers, and identity thieves can use this information to steal your money, access your accounts, or impersonate you online. Only share personal information with trusted websites and people, and use strong passwords that are different for each account. You can use a password manager to help you remember and generate secure passwords
• Double-check and verify links. Before you click on a link, make sure it is from a reliable source and that it leads to where you expect it to go. Some links may contain malware, viruses, or phishing attempts that can harm your computer or trick you into giving away your personal information. You can hover over a link to see the full URL, or use a link scanner tool to check if it is safe
• Use secure public Wi-Fi. When you connect to a public Wi-Fi network, such as at a coffee shop, airport, or hotel, you may expose your online activity and personal information to anyone who is on the same network. Hackers can intercept your data or redirect you to fake websites. To protect yourself, use a VPN (Virtual Private Network) service that encrypts your data and hides your IP address. You can also look for the lock icon or the https prefix in the address bar, which indicate that the website you are visiting is secure
• Use a VPN. A VPN is a service that creates a secure and private connection between your device and the internet. It can help you protect your online privacy, security, and freedom. With a VPN, you can access geo-restricted content, bypass censorship, and prevent your internet service provider, government, or hackers from tracking your online activity. You can choose from many VPN providers, but make sure you do your research and pick a reputable one that suits your needs3. Be careful what you post and share online. Anything you post or share online can be seen by anyone, even if you delete it later. It can also be used against you by cyberbullies, stalkers, or employers. Think before you post or share anything online, and avoid posting or sharing anything that is illegal, offensive, or embarrassing. You can also adjust your privacy settings on social media platforms to control who can see your posts and personal information