What is HTTP (Hypertext Transfer Protocol)?
The Hypertext Transfer Protocol (HTTP) is an application protocol for distributed, collaborative, hypermedia information systems.
Hypertext is the type of structured text that uses logical links (hyperlinks) between nodes containing the text. HTTP is the protocol for exchanging and transferring hypertext.
HTTP functions as a request-response protocol in the client-server computing model. The client submits an HTTP request message to the server. The server, which provides resources such as HTML files and other types of content, and other functions for the client, returns a response message to the client. The response contains completion status information about the request and may contain requested content in the message body.
What is an HTTP request?
An HTTP request is how Internet communication platforms (e.g., web browsers) ask for the information they need to load a website. Each HTTP request made across the Internet carries a series of encoded data with different types of information.
A typical HTTP request includes:
- HTTP version type
- an URL
- an HTTP method
- HTTP request header
- optional HTTP body
What is an HTTP method?
An HTTP method indicates the action that the HTTP request expects from the queried server.
The two most common HTTP methods are GET (it requests information) and POST (it typically indicates that the client is submitting information to the web server, e.g., submitting a password).
Other HTTP methods are:
- PUT – is used to send data to a server or to create/update a resource
- HEAD – it is the same as GET but without the response body
- DELETE – it deletes the specified resource
- PATCH – is used to apply partial modifications to a resource
- OPTIONS – describes the communication options for the target audience
- CONNECT – is used to start a two-way communication with the requested resource
- TRACE – is used to perform a message loop-back test that tests the path for the target resource
What is an HTTP response?
An HTTP response is what web clients receive from an Internet server as an answer to an HTTP request.
A typical HTTP response contains the following:
- an HTTP status code
- HTTP response headers
- optional HTTP body
What is HTTPS?
In addition to HTTP, there is also the Hypertext Transfer Protocol Secure (HTTPS) – a communications protocol for secure communication over a computer network, with vast deployment on the Internet.
HTTPS is the result of layering the Hypertext Transfer Protocol (HTTP) on top of the SSL/TLS protocol, adding security capabilities of SSL/TLS to standard HTTP communications.