PHP: server-side programming language
PHP is a language that is read and executed on the server where the page X / HTML before it is sent to the browser (client) that requests the display. For example, you filled out a form and clicked on the button, the server receives the data sent by the browser, the PHP code processes the data and writes the X / HTML of the new Web page that the Web server then sends to the browser.
The XHTML code of a page can be completely written by using PHP, or PHP code can be inserted at a specific location of a page to complete the X / HTML. It refers to "dynamic" pages where all or certain parts are written in PHP because it is a programming language that modifies or complete the code X / HTML "static" page.
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