Getting Started with cURL

Why do we need to talk to a server?

As we know, when we open a website or use an app, some data is coming from somewhere. That “somewhere” is called a server. A server stores data and responds when someone asks for it.

Usually, browsers talk to servers for us. But as developers, sometimes we want to talk to servers directly to test things or understand how requests work. This is where cURL comes into the picture.

What is cURL? (in very simple terms)

cURL is a command-line tool that helps us send requests to a server and get responses back.

In simple words:

→ cURL lets us talk to a server from the terminal
→ it works without a browser
→ it helps us test and understand how servers respond

You can think of cURL as a way to manually send messages to a server and see what comes back.

Why do programmers need cURL?

Programmers use cURL for many reasons, especially during development and testing.

Some common reasons are:

→ to test APIs
→ to check server responses
→ to debug backend issues
→ to understand request and response flow
→ to work without a browser

cURL gives developers more control and visibility compared to a browser.

Making your first request using cURL

The simplest way to use cURL is to fetch a webpage.

Example command:

→curl https://example.com

What happens here:

→ cURL sends a request to the server
→ the server processes the request
→ the server sends a response back
→ cURL prints the response in the terminal

This is similar to opening a website in a browser, but instead of showing a webpage, cURL shows the raw response.

Understanding request and response

Whenever cURL talks to a server, two things are involved:

Request

→ sent by cURL
→ contains information like where to go and what is needed

Response

→ sent by the server
→ contains status and data

The response usually includes:

→ status code (success or error)
→ data returned by the server

This helps developers understand whether the request worked or failed.

Using cURL to talk to APIs

APIs are servers that return data instead of webpages.

Using cURL, we can directly request data from an API.

Example idea:

→curl https://api.example.com/users

What this does:

→ sends a request to the API
→ receives data (often in JSON format)
→ displays the response in the terminal

This is very useful for testing APIs without building a full frontend.

GET and POST (basic understanding)

When using cURL, we mostly deal with two request types at the beginning.

GET request

→ used to fetch data
→ example: getting a list of users

POST request

→ used to send data
→ example: creating a new user

At the beginner level, understanding these two is enough to get started confidently.

Common mistakes beginners make with cURL

When starting with cURL, beginners often face some common issues:

→ forgetting to add the full URL
→ expecting a webpage instead of raw data
→ getting confused by large responses
→ not understanding error responses
→ trying too many flags at once

The best way is to start simple and slowly explore more options.

Where cURL fits in development

cURL is mostly used in backend and API-related work.

It helps developers:

→ test APIs quickly
→ debug server issues
→ understand how data flows
→ work without a browser

Even though it looks simple, cURL is a very powerful tool once you get comfortable with it.

Conclusion

cURL is a simple yet powerful tool that helps developers communicate with servers directly from the terminal. By starting with basic requests and understanding responses, beginners can build confidence and slowly move towards more advanced use cases.

Instead of being afraid of the terminal, tools like cURL help us understand what actually happens behind the scenes when applications communicate with servers.