In an Introduction to Web Application Development course, various key subtopics should be covered to build a strong foundation. This includes understanding how the internet works and the broader concepts needed to develop web applications.
1. How the Internet Works
The internet is a global system that connects millions of devices, allowing them to communicate and exchange information. Imagine if every bird’s nest represented a computer. The internet would be like connecting all the nests so that every bird could communicate with each other. In technical terms, this connection is called a network. However, just linking the nests isn`t enough; the birds (or computers) need to agree on how to use these connections. This means setting rules for things like how messages are addressed and passed along. These rules are known as protocols in the world of computing.
Client-Server Architecture: When you use your web browser (the client), it sends a request to a server that stores information, such as web pages. The server then processes the request and responds by sending the requested data.
HTTP/HTTPS Protocols: These are the primary methods used for data transfer on the web. HTTP is the protocol for communication between browsers and servers, while HTTPS is a secure version of HTTP that encrypts the data to keep it safe.
DNS (Domain Name System): When you enter a domain name (like www.example.com), the DNS translates that human-readable name into an IP address, which computers use to find each other.
IP Addresses and Ports: Every device connected to the internet has a unique IP address. Just like homes have addresses, devices use IP addresses to find each other. Ports allow a single server to handle multiple types of communication (like web browsing, emails, etc.).
Requests and Responses: When you type a URL in your browser, you are sending a request to a server. The server then processes that request and sends back a response, such as loading a web page.
Web Hosting and Domain Registration: Websites are stored on servers through web hosting, and domain registration allows you to purchase and own a unique website name.
Data Transmission and Packet Switching: If a message (or file) is too large, it needs to be broken down into smaller chunks, called packets, before being sent over the internet. These packets travel independently and are reassembled at the destination.