PHP is a general-purpose scripting language that is widely used for web development and can be embedded into HTML. It was originally created by Danish-Canadian programmer Rasmus Lerdorf in 1993 and released in 1995. The PHP reference implementation is now produced by the PHP Group. PHP stands for "PHP: Hypertext Preprocessor," which is a recursive acronym. PHP code is executed on the server, generating HTML which is then sent to the client. PHP files can contain text, HTML, CSS, JavaScript, and PHP code. PHP is free to download and use.

Some key features of PHP include:

• Versatility: PHP is a versatile scripting language that is great for both beginners and experts. It is regularly updated to follow the latest technology trends.

• Compatibility: PHP can be deployed on most web servers on a variety of operating systems and platforms.

• Web Development: PHP is especially suited for server-side web development, in which case PHP generally runs on a web server. It can generate dynamic page content, collect form data, send and receive cookies, and add, delete, and modify data in databases.

• Content Management Systems: Many popular content management systems, such as WordPress, Drupal, Joomla, and Magento, are built in PHP.

While PHP is still relatively popular among software developers, it is a language in decline with so much choice now available. According to PYPL (PopularitY of Programming Language), PHP is ranked as the sixth most popular coding language in the world. The TIOBE index ranks PHP as the 10th most popular programming language currently available.