Web Servers

Web Server: Web server is a program which processes the network requests of the users and serves them with files that create web pages. This exchange takes place using Hypertext Transfer Protocol (HTTP).

Basically, web servers are computers used to store HTTP files which makes a website and when a client requests a certain website, it delivers the requested website to the client. For example, you want to open Facebook on your laptop and enter the URL in the search bar of google. Now, the laptop will send an HTTP request to view the facebook webpage to another computer known as the webserver. This computer (webserver) contains all the files (usually in HTTP format) which make up the website like text, images, gif files, etc. After processing the request, the webserver will send the requested website-related files to your computer and then you can reach the website.

Different websites can be stored on the same or different web servers but that doesn’t affect the actual website that you are seeing in your computer. The web server can be any software or hardware but is usually a software running on a computer. One web server can handle multiple users at any given time which is a necessity otherwise there had to be a web server for each user and considering the current world population, is nearly close to impossible. A web server is never disconnected from the internet because if it was, then it won’t be able to receive any requests, and therefore cannot process them.

Key Functions of a Web Server:

1. Handling Requests: A web server waits for incoming requests from clients (typically browsers) and processes them.
2. Serving Content: The server sends back the requested web page (or other resources like images, videos, or documents) to the client.
3. Processing Dynamic Content: Some web servers can run server-side scripts (like PHP, Python, or Node.js) to generate dynamic content, such as interactive pages, user accounts, etc.
4. Handling Multiple Requests: A good web server can handle multiple requests from various users simultaneously.

Web Server Components:

• Hardware: The physical computer or machine where the server runs. It could be in a data center or hosted remotely in the cloud.
• Software: The web server software that runs on the machine to handle requests. There are many web servers available in the market both free and paid.Some of the popular web server software include:
  • Apache HTTP Server: One of the most widely used open-source web servers.
  • Nginx: A high-performance web server known for its ability to handle many simultaneous connections.
  • IIS (Internet Information Services): A web server developed by Microsoft, often used with Windows-based systems.
  • LiteSpeed: A commercial web server known for its speed and security features.

How Web Servers Work:

1. Client Makes a Request: When you enter a URL in your browser’s address bar, the browser sends an HTTP request to the web server.

2. DNS Resolution: The domain name (e.g., www.example.com) is resolved into an IP address via DNS. This helps your browser locate the web server.

3. Request Handling: The web server receives the HTTP request and decides what action to take based on the URL. It may:

   • Serve static content (like HTML files, images, etc.)
   • Process server-side scripts (like PHP, ASP.NET) to generate dynamic content
   • Access databases (like MySQL, PostgreSQL) for data

4. Response to Client: Once the web server has the requested content, it sends it back to the browser in an HTTP response. This response includes:

   • Status Code: Indicates whether the request was successful (200 OK), or if there was an error (404 Not Found).
   • Content: The requested resource, such as an HTML page, image, or JSON data.

5. Browser Displays Content: The browser processes the response, renders the page, and shows it to the user.