Hypertext Transfer Protocol (HTTP) is an application layer protocol that facilitates the transfer of data between a client (usually a web browser) and a server (where web content is hosted) over the internet. It forms the foundation of data communication on the World Wide Web.
Key characteristics of HTTP include:
Statelessness: Each request from the client to the server is independent and contains all the information necessary for the server to fulfill the request. The server doesn’t retain any information about past requests from the same client.
Request-Response Model: Clients send requests to servers, and servers respond with the requested data. A request typically includes a method (GET, POST, etc.), a URL, headers, and optional data.
Methods: HTTP defines several methods to specify the desired action to be performed on a resource. The most common methods are GET (retrieve data), POST (submit data to be processed), PUT (update a resource), and DELETE (remove a resource).
Status Codes: Servers respond to requests with status codes indicating the outcome of the request. Examples include 200 (OK), 404 (Not Found), and 500 (Internal Server Error).
Headers: Both requests and responses include headers containing additional information about the request/response or the data being transferred.
URLs: Uniform Resource Locators (URLs) are used to identify and locate resources on the web. URLs consist of a protocol identifier (http://), domain name, and optional path.
Caching: HTTP supports caching, allowing clients to store copies of responses for quicker access and reduced server load.
HTTP operates in a client-server model, where clients (typically web browsers) initiate requests for resources (web pages, images, etc.) from servers. The servers process these requests and respond with the requested data, which is then displayed by the client.
In recent years, an enhanced version called HTTP/2 has been introduced, designed to improve performance by reducing latency and optimizing data transmission. Additionally, HTTPS (HTTP Secure) uses encryption to secure the data transmitted between the client and the server, ensuring privacy and data integrity.
Overall, HTTP plays a fundamental role in enabling the browsing and interaction experience on the internet.