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HTTP vocabulary

Client

A computer used by a user to connect to a network and make requests to servers.

CRUD

The four basic operations of persistent storage, in computer programming.

These operations map to the four main HTTP methods: create/POST, read/GET, update/PUT, and DELETE/DELETE.

HTTP

The underlying network protocol that enables transfer of hypermedia documents on the Web, typically between a browser and a server so that humans can read them.

HTTP header

Allows clients and servers to pass additional information to each other with HTTP requests and HTTP responses.

HTTP messages

How data is exchanged between a client and a server.

There are two types of HTTP messages: HTTP requests, sent by a client to a server, and HTTP responses, sent from the server to the client.

HTTP methods / verbs

Options given to a client for requesting or manipulating resources.

Options include: GET, HEAD, POST, PUT, DELETE, CONNECT, OPTIONS, TRACE, and PATCH.

HTTP request

HTTP messages sent by the client to initiate an action on the server.

HTTP response

HTTP messages sent from a server to the client, which can include a representation of a resource, a success message, or an error message.

HTTP response status codes

HTTP messages sent from a server indicating whether a client's HTTP request is successful.

Idempotent / idempotency

An HTTP method is idempotent if an identical request can be made more than once with the same effect without changing the state of the server. A GET method is considered idempotent. A POST (create) method is not considered idempotent.

Protocol

A system of rules that define how data is exchanged within or between computers.

Server

A computer that serves many kinds of information to a user or client machine.

Stateless

In the client-server model, a stateless protocol means that the server does not keep any data (state) between two requests.

This is in contrast to a stateful protocol, which does keep data (state) between separate requests.

HTTP is a stateless protocol.

Sources
  • Fielding, R., Gettys, J., Mogul, J., Frystyk, H., Masinter, L., Leach, P., and T. Berners-Lee, "Hypertext Transfer Protocol -- HTTP/1.1", RFC 2616, DOI 10.17487/RFC2616, June 1999, https://www.rfc-editor.org/info/rfc2616.
  • MDN Web Docs
  • Richardson, L., & Ruby, S. (2013). RESTful web apis.