“PHP is a widely used, general-purpose scripting language that was originally designed for web development to produce dynamic web pages. For this purpose PHP code is embedded into the HTML source document and interpreted by a web server with a PHP processor module, which generates the web page document.”

– PHP @ Wikipedia

Basic Principles of PHP

  • PHP is a server-side programming language: it runs on a web server.
  • PHP pages typically contain a mix of HTML and PHP code.
  • When a web server receives a request for a PHP page, the server first processes any PHP code in the page.
  • The PHP code may generate text output, including HTML tags — this technique is sometimes known as dynamic content
  • The combined results — static HTML, and dynamic content generated by PHP — is sent back to the user
  • To the user, all content looks like static HTML: dynamic content is indistinguishable from static content
  • The user will never see PHP code: PHP code never appears in the browser — PHP runs on the server, and if the PHP generates dynamic content, the user sees that content, but never the PHP code itself

Uses for PHP

  • Use PHP for a wide variety of web technologies: e-commerce, blogs, automated email, RSS aggregation, etc.

See Also