PHP is a coding language that enables users to do more with web experiences. It allows for unique information to be sent from a server specific to the server owner's wishes. Among its capabilities is the ability to send specific HTML files to a user requesting a new page from the server. JavaScript is another coding language. It allows for more diverse interaction experiences on a website. In contrast with PHP that can manage HTML files, JavaScript usually only has to do with content within HTML files.
Maintaining a website should be a regularly occurring activity to keep a website up to standards and secure. Making sure that all website functions are still acting correctly as well as regularly checking guidelines for websites ensures that no problems arise, and future problems may be accounted for.