HTTP is a method for encoding and transporting data between a client and a server. It is a request/response protocol: clients issue requests and servers issue responses with relevant content and completion status info about the request. HTTP is self-contained, allowing requests and responses to flow through many intermediate routers and servers that perform load balancing, caching, encryption, and compression.
A basic HTTP request consists of a verb (method) and a resource (endpoint). Below are common HTTP verbs:
Verb | Description | Idempotent* | Safe | Cacheable |
-------|-------------------------------|-------------|------|-----------------------------------------|
GET | Reads a resource | Yes | Yes | Yes |
POST | Creates a resource or trigger | No | No | Yes if response contains freshness info |
PUT | Creates or replace a resource | Yes | No | No |
PATCH | Partially updates a resource | No | No | Yes if response contains freshness info |
DELETE | Deletes a resource | Yes | No | No |
HTTP is an application layer protocol relying on lower-level protocols such as TCP and UDP.