If you're starting your web development journey, grasping the "how" and "why" of the web is just as important as learning HTML, CSS, or JavaScript.

You'll gain all the essential knowledge you need to get started with web development.

How does the Internet work?

The Internet is the backbone of the Web, the technical infrastructure that makes the Web possible. At its most basic, the Internet is a large network of computers which communicate all together.

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Web Fundamentals: Your Guide to the Building Blocks of the Web in 2024

The web has evolved dramatically, but its core principles remain essential for anyone looking to understand or build for the digital world. This guide breaks down the fundamental concepts of the web, from basic definitions to the technologies that power the modern online experience.

1. The World Wide Web (WWW): An Interconnected Information System

The World Wide Web, often simply called the Web, is a vast system of interconnected documents and resources linked together and accessed via the Internet (the underlying network infrastructure). Think of it as a giant library where information is shared and accessed globally.

• Key Components:
  • Resources: These are the building blocks of the web – web pages, documents, images, videos, and other digital content.
  • URLs (Uniform Resource Locators): Unique addresses that identify each resource, like a street address for a webpage (e.g., https://www.example.com/about).
  • HTTP/HTTPS (Hypertext Transfer Protocol): The communication rules (protocols) that govern how web browsers and servers exchange information. HTTPS adds a layer of security through encryption.
  • Web Servers: Computers that store and serve web resources.
  • Web Browsers: Software applications (like Chrome, Firefox, or Edge) that allow users to access and interact with web resources.

2. Web Pages, Websites, and Web Apps: Understanding the Differences

• Web Page: A single document, typically written in HTML, that can display text, images, videos, and other media.
• Website: A collection of related web pages, usually linked together under a single domain name. Think of it as a book with multiple chapters.
• Web App (Web Application): A more interactive and dynamic type of website that provides functionalities similar to desktop or mobile applications. Examples include Gmail, Google Docs, and many modern social media platforms. Web apps often leverage advanced technologies like JavaScript frameworks and APIs to provide a rich user experience.

3. Building Web Pages: The Trifecta of HTML, CSS, and JavaScript

Creating web pages involves three core technologies:

• HTML (Hypertext Markup Language): The foundation. HTML provides the structure and content of a web page, defining elements like headings, paragraphs, images, and links. It's like the skeleton of a building.
• CSS (Cascading Style Sheets): The stylist. CSS controls the presentation and visual appearance of a web page, handling aspects like colors, fonts, layout, and responsiveness (how the page adapts to different screen sizes). It's like the interior design and decoration of a building.
• JavaScript: The brains. JavaScript adds interactivity and dynamic behavior to web pages. It enables things like form validation, animations, interactive maps, and much more. It's like the electrical wiring and smart home features of a building, making it functional and dynamic.

4. Web Browsers: Your Window to the Web

Web browsers are essential software applications that allow you to access and interact with the World Wide Web. Popular browsers in 2024 include:

• Google Chrome
• Mozilla Firefox
• Microsoft Edge
• Safari
• Brave
• Opera

How Browsers Work: When you enter a URL, the browser sends a request to the web server hosting that resource. The server sends back the necessary files (HTML, CSS, JavaScript, images, etc.), and the browser interprets these files to render (display) the web page on your device.

5. Servers: The Powerhouses of the Web

Servers are specialized computers that store, process, and deliver web resources to clients (like your web browser). There are various types of servers, each with a specific role:

• Web Servers: Designed to serve web pages and other web content. Popular web server software includes Apache, Nginx, and Microsoft IIS. They handle requests via HTTP/HTTPS, interact with databases, and deliver the requested resources.
• Mail Servers: Handle email sending, receiving, and routing. They use protocols like SMTP (Simple Mail Transfer Protocol), POP3 (Post Office Protocol version 3), and IMAP (Internet Message Access Protocol).
• File Servers: Allow users to store, access, and manage files over a network. They often use FTP (File Transfer Protocol) or SFTP (Secure File Transfer Protocol).

6. Databases: Organizing the Web's Information

Databases are organized collections of data that make it easy to store, retrieve, manage, and update information. They are crucial for most dynamic websites and web applications.

• Relational Databases (SQL): Store data in tables with rows and columns, establishing relationships between tables. They are ideal for structured data and use SQL (Structured Query Language) for data manipulation. Examples: MySQL, PostgreSQL, Oracle, SQL Server.
• Non-Relational Databases (NoSQL): Store data in more flexible formats like documents, key-value pairs, or graphs. They are well-suited for large volumes of unstructured or semi-structured data. Examples: MongoDB, Cassandra, Redis, Couchbase.

7. Client-Server Architecture: The Foundation of Web Interaction

The web fundamentally operates on a client-server architecture.

• Client: Your web browser, requesting resources.
• Server: The computer storing and delivering the resources.

The browser interprets the received data using:

• DOM (Document Object Model) Interpreter: Parses the HTML structure.
• CSS Interpreter: Applies the styles defined in CSS.
• JavaScript Engine: Executes JavaScript code to add interactivity.

8. Types of Web Development: Front-End, Back-End, and Full-Stack

Web development is typically divided into three main areas:

• Front-End Development: Focuses on the user interface (UI) and user experience (UX) – everything the user sees and interacts with directly in the browser. Front-end developers use HTML, CSS, and JavaScript, often with frameworks like React, Angular, or Vue.js.
• Back-End Development: Deals with the server-side logic, databases, and APIs that power the front-end. Back-end developers work with server-side languages like Python, Java, Node.js, PHP, or Ruby and database technologies.
• Full-Stack Development: Encompasses both front-end and back-end development. Full-stack developers are proficient in a range of technologies, allowing them to work on all aspects of a web application. Popular full-stack combinations include MERN (MongoDB, Express.js, React, Node.js), MEAN (MongoDB, Express.js, Angular, Node.js), and others.

9. Web Hosting: Making Your Website Accessible

Web hosting is the service that makes your website or web application accessible to users on the internet. Web hosting providers offer space on their servers (data centers) to store your website's files and make them available 24/7. Popular hosting options include shared hosting, VPS hosting, dedicated servers, and cloud hosting.

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