What is post?

A POST is a type of request you send from a web browser or app to a server to tell it to create or update something, like submitting a form, uploading a picture, or adding a comment. Unlike a GET request that only asks for data, a POST sends data to the server for it to process.

Let's break it down

  • Client: Your computer, phone, or any device that makes the request.
  • POST request: The message that includes a URL (where to send it) and a body (the data you’re sending).
  • Server: The computer that receives the request, reads the data, and decides what to do (save it, change something, etc.).
  • Response: After processing, the server sends back a reply, often confirming success or reporting an error.

Why does it matter?

POST lets you interact with websites and apps in a dynamic way. It’s how you create new accounts, post updates, buy items, or upload files. Without POST, the web would be limited to just reading information, not changing or adding anything.

Where is it used?

  • Submitting login forms (username/password)
  • Registering for a new account
  • Posting comments or messages on social media
  • Uploading photos, videos, or documents
  • Adding items to an online shopping cart
  • Sending data from mobile apps to cloud services

Good things about it

  • Secure for data: Data is sent in the request body, not visible in the URL, so it’s less exposed in browser history.
  • Handles large data: You can send more information (files, long text) than with a GET request.
  • Creates/updates: Perfect for actions that change the server’s state, like adding a new record to a database.
  • Standardized: All modern web browsers and APIs support POST, making it widely compatible.

Not-so-good things

  • Not cache-friendly: Browsers and proxies usually don’t store POST responses, so repeated requests can be slower.
  • Can be misused: If not protected, attackers might send unwanted POST requests (CSRF attacks).
  • No bookmarkability: Because data isn’t in the URL, you can’t bookmark a POST request to replay it later.
  • Potentially larger payloads: Sending big files can consume more bandwidth and require careful handling on the server side.