Getting Started with cURL
I believe writing makes learning easier so I share simple Tech notes with diagrams
Introduction -
Before we talk about cURL, let us take one small step back. Every time you open a website, your browser is talking to a server somewhere on the internet. The server listens, understands the request, and sends something back a webpage, data, or an error.
cURL is simply a way to have that conversation from the terminal without a browser.
What Is cURL ?
cURL is a command-line tool that lets you send requests to a server and see the response. Imagin it like Browser → talks to server with a UI but cURL → talks to server using text commands.
With cURL you can say “Hey server give me this page” or “Here’s some data please save it” And the server replies directly in your terminal.
Why Programmers Need cURL -
Programmers use cURL because it is Simple, Available on almost every system and honest (no hidden behavior like browsers)
Common uses:
Testing APIs
Checking if a server is responding
Debugging backend issues
Learning how HTTP actually works
If you understand cURL, you understand how programs talk over the internet.
Making Your First Request Using cURL -
Let’s start with the simplest possible example. Open your terminal and run:
curl https://example.com
What just happened?
cURL sent a request to the server
The server responded with HTML
cURL printed that response in your terminal
You just fetched a webpage without using a browser.
Understanding Request and Response -
Every HTTP conversation has two parts:
1. The Request
This is what you send to the server —>Where you want to go (URL) & What you want (GET or POST)
In the example:
curl https://example.com
You are saying that Please GET this page
2. The Response
This is what the server sends back —> Status (success or error) & Data (HTML, JSON, text)
If the request is successful, you usually get:
Status: 200 (OK)
Some content printed in your terminal
cURL doesn’t decorate the response it shows you the raw result.
Introducing GET and POST -
For now you only need to know two methods
GET
POST
GET is used to fetch data, Example:
curl https://api.example.com/users
This means Give me the users.
POST is used to send data, creating something, sending form data and submitting information to an API. We won’t go deep yet just know that POST exists and is used to send data.
Using cURL to Talk to APIs -
APIs are just servers that return data instead of webpages. Example:
curl https://api.github.com
Instead of HTML you will see JSON. This is extremely useful when:
You are building backend services
You want to test an API quickly
You don’t want to write code just to check a response
cURL is often the first tool developers reach for when debugging APIs.
Common Mistakes Beginners Make with cURL -
Expecting a pretty output - cURL shows raw data & No formatting, no colors, no UI. That’s a feature, not a problem.
Using too many flags too early - cURL has many options, but you don’t need them at the start. Begin with Simple GET requests & Understanding responses. Depth comes later
Confusing browser behavior with cURL - Browsers add headers, cookies, and extra logic. cURL does exactly what you tell it nothing more. That’s why it is trusted for debugging.
Conclusion -
cURL is not a “tool to memorize”.
It’s a conversation starter with servers. Once you’re comfortable with:
Sending a request
Reading a response
Understanding what the server says back
You’ll feel much more confident working with:
APIs
Backend systems
Networked applications
Start simple and use cURL often. The rest will come naturally.
