PHP is a computer programming language that was developed specifically for web development and web hosting. If you are new to the concept of programming languages, you may want to scan a the Internet for tutorials or general concepts related to programming. Essentially, a programming language is a series of instructions read by a computer. The computer interprets the instructions into "machine code" and then performs the actions specified by the programmer.
PHP is an open-source programming language that is centrally maintained and distributed by a core team and many contributing developers. It began in 1995 when Rasmus Lerdorf built a set of scripts to track access to his online resume. He called this set of tools "Personal Home Page Tools" or PHP. The syntax for PHP is similar to C++ and Perl. It lacks just two features (operator overloading and polymorphism) from being a true object oriented programming language, although it does implement classes with constructors and inheritance.
Because PHP was designed from the ground up to be a web programming language, it is especially easy to integrate into an HTML document. You actually start with a web page, and then use certain instructions to switch in and out of PHP. PHP integrates especially well with the open-source database MySQL.
PHP web hosting is simply offering the PHP "parser" as part of a web hosting plan. PHP typically acts as a "module" for a web server, and the most common web server used in web hosting applications is the Apache web server. When a person requests a document from the web server, it first filters it through PHP and then gives the output from PHP to the individual requesting the web document.
At 24shells.net, we offer PHP with all our web hosting plans. We also offer our customers the opportunity to go even further to extend and customize PHP's functionality to fit their needs perfectly. Our root access web hosting plan gives each user their own dedicated operating system and root access, enabling them to compile virtually any module into PHP or even customize the PHP code itself.