What is a PHP file?

A PHP file is a file that is used to display a web page. The PHP file takes the place of the common .html extension that the internet saw a lot of in the 90's. The PHP file extension is .php, without this, the server will not be able to handle the request correctly unless apache is custom modified in order to handle the request. PHP allows web developers to write web page software that dynamically connects to databases and perform other functions that may automatically change the web pages display over time and based on user input. PHP is the choice language for most web developers because of it's ease of use, multitude of useful functions and ability to handle traffic without consuming excessive server resources. This makes it the best choice for programming websites large and small.