Definition
HTTP defines request methods (GET, POST, …), headers, status codes, and bodies. HTTPS wraps HTTP in TLS encryption for security.
Every web page load and REST API call uses HTTP under the hood.
In simple terms
HTTP is the postal system of the internet — envelopes (requests) with addresses (URLs), delivery status (200 OK, 404), and optional contents (JSON body).
Where you see it
- Browsers fetch HTML, CSS, and JS over HTTP.
- LLM API calls are HTTPS POST requests with JSON.
How it works
1.Client request
Method, URL, headers, optional body.
2.Server response
Status code, headers, body.
3.Stateless
Each request is independent; cookies/tokens carry session state.
Why it matters
- HTTP literacy is required to debug APIs, caches, and web performance.
Often confused
HTTP and HTTP/2 are completely different protocols.
HTTP/2 optimizes the same semantics with multiplexing and header compression.