Getting Started with cURL
Learn how to talk to servers using the cURL Command
If you are learning backend development, APIs, or even basic web concepts, you will hear the word cURL again and again. At first it looks scary a black terminal, strange commands, and confusing responses.
This blog is written to remove that fear.
No overload. Just clear thinking.
❀ Before cURL: What is a Server?
⤷ A server is simply a computer that is always connected to the internet and waits for requests.
Examples of what servers do:
Send a webpage (HTML, CSS, JS)
Return user data from a database
Accept form submissions
Provide APIs for mobile apps
Whenever you:
Open a website
Submit a login form
Scroll Instagram
You are talking to a server.
❀ How Do We Talk to a Server?
⤑ To talk to a server, we send a request.
That request contains:
What we want (data, page, action)
Where we want it from (URL)
Sometimes extra data (login info, form data)
⤑ The server then sends back a response.
That response contains:
Status (success or failure)
Data (HTML, JSON, text, etc.)
❀ Where Does cURL Come In?
⤷ Normally, browsers send requests for us.
But programmers often want to:
Test APIs
Debug backend issues
Call a server without a browser
Automate requests
This is where cURL is used.
⤑ cURL is a tool that lets you send requests to a server from the terminal.
Think of it as:
Terminal → Server → Response
❀ What is cURL ?
⤑ cURL = Command Line URL tool
⤑ cURL is a way to send messages to a server using text commands.
No UI. No buttons. Just pure communication.
❀ Why Programmers Need cURL ?
⤷ Programmers use cURL because:
It works everywhere (Linux, Mac, Windows)
No browser required
Perfect for backend and API testing
Helps understand how HTTP really works
❀ Understanding Request and Response
⤑ Request (What You Send)
A basic HTTP request includes:
Method (GET / POST)
URL
Headers (optional for now)
Body (only for POST)
Example :
GET / HTTP/1.1
Host: prakashtsx.me
⤑ Response (What You Get Back)
A response includes:
Status code (200, 404, 500)
Headers
Data (HTML, JSON, text)
Example :
HTTP/1.1 200 OK
Content-Type: text/html
<html>...</html>
❀ Status Codes :
200 → Success
404 → Not Found
500 → Server Error
❀ Using cURL to Talk to APIs
APIs usually return JSON, not HTML.
Example:
We will see JSON data in response.
This is how:
Frontend talks to backend
Mobile apps talk to servers
Services talk to other services
❀ GET vs POST (Only What We Need)
⤷ GET
Used to fetch data
Default method in cURL
curl https://api.example.com/users
⤷ POST
- Used to send data
curl -X POST https://api.example.com/login
❀ Browser Request vs cURL Request (Conceptual)
Browser:
- UI + request + rendering
cURL:
- Only request + response
Same protocol. Same server. Different interface.
❀ Where cURL Fits in Backend Development
cURL helps you:
Test APIs before frontend exists
Debug server issues
Understand HTTP deeply
Think like a backend engineer
