HTTP Methods and Their Use Cases

The Hypertext Transfer Protocol (HTTP) is the foundation of communication on the web. Every time you interact with a website—whether you’re browsing, submitting a form, or uploading a file—your browser sends an HTTP request to the server. This request specifies an HTTP method, which tells the server what kind of action is being requested.

1. GET

• Purpose: Retrieve data from a server.

• Characteristics:

  • Safe (does not modify data).

  • Can be cached by browsers.

  • Appends data to the URL (as query parameters).

• Example Use Cases:

  • Loading a webpage (GET /index.html).

  • Searching on Google (GET /search?q=chatgpt).

  • Fetching product details in an e-commerce store.

2. POST

• Purpose: Submit data to the server (usually to create or update a resource).

• Characteristics:

  • Not cached by default.

  • Data is sent in the request body (not in URL).

  • Can change server-side data.

• Example Use Cases:

  • Logging into a website (sending username & password).

  • Submitting a contact form.

  • Uploading an image or file.

3. PUT

• Purpose: Update or replace an existing resource on the server.

• Characteristics:

  • Idempotent (repeating the same request gives the same result).

  • Sends complete resource data (not partial).

• Example Use Cases:

  • Updating a user profile (PUT /users/123).

  • Replacing an article in a blog system.

4. PATCH

• Purpose: Partially update an existing resource.

• Characteristics:

  • Unlike PUT, only the changed fields are sent.

  • More efficient for small updates.

• Example Use Cases:

  • Changing only a user’s email address (PATCH /users/123).

  • Updating the price of a product without altering other details.

5. DELETE

• Purpose: Remove a resource from the server.

• Characteristics:

  • Idempotent (deleting the same resource multiple times has the same effect).

• Example Use Cases:

  • Deleting a blog post (DELETE /posts/45).

  • Removing an item from a shopping cart.

6. HEAD

• Purpose: Retrieve metadata (headers) of a resource without fetching the body.

• Characteristics:

  • Similar to GET but only returns headers.

  • Useful for checking if a resource exists or validating cache.

• Example Use Cases:

  • Checking if an image exists on a server before downloading.

  • Verifying last-modified date of a file.

7. OPTIONS

• Purpose: Find out which methods are allowed for a resource.

• Characteristics:

  • Returns supported HTTP methods in the Allow header.

  • Often used in CORS (Cross-Origin Resource Sharing).

• Example Use Cases:

  • Browser checking which methods are supported before making a request.

  • Security testing of APIs.

8. CONNECT (less commonly used)

• Purpose: Establish a tunnel to the server (often for HTTPS via a proxy).

• Example Use Case:

  • Secure SSL/TLS connections through an HTTP proxy.

9. TRACE (rare, mostly disabled for security)

• Purpose: Echoes the received request for debugging.

• Example Use Case:

  • Debugging or diagnosing request path (though usually disabled due to security risks like XSS).

Real-World Analogy

Think of HTTP methods like actions you perform at a library:

• GET → Reading a book.

• POST → Donating a new book.

• PUT → Replacing an old book with a new edition.

• PATCH → Updating a single chapter in a book.

• DELETE → Removing a book from the library.

• HEAD → Checking only the book’s metadata (title, author).

• OPTIONS → Asking the librarian what services you can use.

Why HTTP Methods Matter?

• They define clear communication between client and server.

• They make APIs RESTful and predictable.

• They ensure security and efficiency in web applications.

• They help developers build scalable systems where each action has a defined purpose.