PHP is a scripting language originally created for web development and now used as a general purpose programming language. Key developers include Rasmus Lerdorf, Zeev Suraski, and Andi Gutmans. PHP scripts can be embedded into HTML pages and is commonly used to connect web applications with databases. PHP is influenced by C and supports features like functions, arrays, and object-oriented programming. It provides a large standard library for common tasks like string handling, dates, files, and working with databases.