cookies

Client

A client is a piece of computer hardware or software that accesses a service made available by a server. The server is often (but not always) on another computer system, in which case the client accesses the service by way of a network. The term applies to programs or devices that are part of a client-server model.

Cookies

A cookie is a small text file that is stored on your computer when you visit some websites. A cookie is used to remember settings from your last visit to a website. For example Amazon use cookies to help identify you when you revisit the site.

Server

A server is a running instance of an application (software) capable of accepting requests from the client and giving responses accordingly. Servers can run on any computer including dedicated computers, which individually are also often referred to as "the server".

PHP

PHP is a server-side scripting language created in 1995 and designed for web development but also used as a general-purpose programming language