PHP (Hypertext Preprocessor) is a popular server-side scripting language that is primarily used for web development. It is an open-source, general-purpose language that is designed to be embedded into HTML code and executed on a web server. PHP can generate dynamic web pages, process form data, interact with databases, and perform a wide range of other server-side tasks. It is supported by most web servers and can be used in conjunction with a variety of web development frameworks, content management systems (CMS), and other technologies. PHP is a widely used language, powering many popular websites such as Facebook, Wikipedia, and WordPress. It has a large community of developers who contribute to its ongoing development and improvement, making it a valuable tool for web developers.