Taking the Next.js step - Intro

I. The Internet (The Big Picture)

What is it? A global network of interconnected computer networks using standardized communication protocols.

Key Concepts:

IP Address: A unique numerical identifier assigned to each device on a network (like a house address). Example: 192.168.1.1 (IPv4), 2001:0db8:85a3:0000:0000:8a2e:0370:7334 (IPv6).

Domain Name: A human-readable name for a website that is translated to an IP address by DNS servers (like a street name). Example: google.com.

DNS (Domain Name System): The "phonebook" of the internet. It translates domain names into IP addresses.

Protocols: Sets of rules that govern communication between devices. Examples:

HTTP (Hypertext Transfer Protocol): The foundation of data communication for the World Wide Web.

HTTPS (HTTP Secure): A secure version of HTTP that uses encryption.

TCP/IP (Transmission Control Protocol/Internet Protocol): The basic communication protocols of the internet.

How it works (simplified): You type a domain name in your browser -> DNS finds the corresponding IP address -> your browser sends a request to the server at that IP address -> the server sends back the website data -> your browser displays the website.

II. Web Applications (What We Build)

Definition: Software applications that run on web servers and are accessed through web browsers.

Types:

Static Websites: Display the same content to all users. Primarily HTML, CSS, and some client-side JavaScript.

Dynamic Websites: Generate content dynamically based on user interactions, data from databases, etc. Requires server-side processing.

III. Front-End vs. Back-End (The Two Sides of the Coin)

Front-End (Client-Side):

What it is: The part of the application that users interact with directly in their browsers.

Technologies:

HTML, CSS, JavaScript (You already know these!)

Frameworks/Libraries: Tools that simplify complex front-end development. Examples: React, Angular, Vue.js. We will be focusing on React, specifically using the Next.js framework.

Responsibilities: User interface, user experience, handling user input, making requests to the back-end.

Back-End (Server-Side):

What it is: The part of the application that runs on a server and handles data processing, logic, and database interactions.

Technologies:

Programming Languages: Python, Java, Node.js (JavaScript), PHP, Ruby, etc.

Frameworks: Express.js (Node.js), Django (Python), Ruby on Rails (Ruby), etc.

Databases: MySQL, PostgreSQL, MongoDB, etc.

Servers: Apache, Nginx, etc.

Responsibilities: Handling requests from the front-end, processing data, interacting with databases, implementing business logic, ensuring security.

IV. Databases (Storing the Data)

What is it? An organized collection of structured information, or data, typically stored electronically in a computer system.

Types (briefly):

Relational Databases (SQL): Store data in tables with rows and columns. Use SQL (Structured Query Language) for querying. Examples: MySQL, PostgreSQL, SQL Server.

NoSQL Databases: Store data in various formats, such as documents (JSON-like), key-value pairs, or graphs. More flexible than relational databases. Examples: MongoDB, Cassandra.

Key Concepts:

Tables: Collections of related data.

Rows (Records): Individual entries in a table.

Columns (Fields): Attributes of each entry.

Queries: Requests for data from the database.

V. How it All Works Together (A Typical Web Request)

User interacts with the front-end (e.g., clicks a button).

Front-end JavaScript sends a request (e.g., using fetch or axios) to the back-end server (using HTTP). In applications built with Next.js, this request might be to an API route handled by Next.js itself.

Back-end server receives the request, processes it (e.g., performs calculations, retrieves data from the database).

Back-end server sends a response back to the front-end (usually in JSON format).

Front-end JavaScript receives the response and updates the user interface. In Next.js applications, this update might involve re-rendering components based on the received data.

VI. Next.js: A Note

Next.js is a powerful React framework that enhances React development by providing features like server-side rendering, file-based routing, and API routes. It simplifies building production-ready web applications by handling some server-side aspects, making the development process more efficient.