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Souvik Guha Roy
Souvik Guha Roy

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Getting Started with cURL

#chaicode #webdev #programming #networking

In this blog, we’ll cover:

  • What a server is and why we need to talk to it
  • What cURL is (in very simple terms)
  • Why programmers use cURL
  • Making your first request using cURL
  • Understanding requests and responses with cURL
  • Common mistakes beginners make while using cURL

What is a Server?

Think of a server like your friend.

You ask your friend for some money:

  • If your friend is in a good mood and has money, they say “Sure”
  • Otherwise, they say “No”

A server works in a very similar way.

👉 A server is a hardware or software system that receives requests over a network, processes them, and sends back a response.

Every time you open a website, upload a photo, or log in to an app — you’re talking to a server.

Why Do We Need to Talk to a Server?

Servers are important because they allow us to:

  • Get data (fetch posts, videos, products, etc.)
  • Send data (forms, messages, login details)
  • Update data (edit profile, change password)
  • Delete data (remove posts or accounts)

For example, you cannot upload a photo to social media without communicating with a server.
Your app sends the photo → the server stores it → and responds with success or failure.

What is cURL?

cURL stands for Client URL.

It is a command-line tool (like ping or ipconfig) used to send requests and transfer data between your computer and a server using a URL.

You can run cURL using any Command Line Interface (CLI) such as:

  • Command Prompt (cmd)
  • PowerShell
  • Terminal
  • Warp

In simple words:
👉 cURL lets you talk to servers directly from the command line.

Why Do Programmers Use cURL?

cURL is widely used by programmers because:

  • It allows quick HTTP requests
  • It supports GET, POST, PUT, DELETE, and more
  • It’s lightweight and fast
  • Backend developers use it heavily to test APIs
  • No browser or UI required — just commands

Practical Examples of cURL

To use cURL, open a CLI on your device (cmd, PowerShell, Terminal, Warp, etc.).

1. Fetching a Website

This command fetches the HTML content of a website:

curl https://google.com
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You’ll see raw HTML returned by the server.

2. Sending a GET Request

A GET request is used to retrieve data from a server.

curl https://dummyjson.com/products
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If you check the response, you’ll receive a list of products in JSON format.

3. Sending a POST Request

A POST request is used to send or update data on a server.

curl -X POST https://httpbin.org/anything
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This sends a POST request, and the server responds with details about the request it received.

Understanding Request and Response

When you use cURL:

  1. You send a request (URL + method + data)
  2. The server processes it
  3. The server sends a response, which includes:
  • Status code (200, 404, 500, etc.)
  • Headers
  • Response body (data or message)

This request–response cycle is the foundation of APIs.

Common Mistakes Beginners Make with cURL

Here are some common mistakes to watch out for:

  • ❌ Writing URLs incorrectly or without quotes when required
  • ❌ Ignoring the HTTP status code in the response
  • ❌ Sending invalid JSON data
  • ❌ Forgetting flags like -X, -H, or -d
  • ❌ Mixing up GET and POST requests

Final Thoughts

cURL might look scary at first, but once you understand it, it becomes a powerful tool for learning how servers and APIs actually work.

If you’re a beginner in backend development, learning cURL is 100% worth it.

Happy coding 🚀

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