I’m looking to make a database site using PHP, MySQL and wondering what exactly is CMS? For instance, PHP-Nuke is software? Or is it just code? Confused. Can someone simplify this for me?
PHP: PHP is a language for web content. Unlike HTML which is a markup language (a formatting language for text, pictures, etc.), PHP is a bonafide programming language with conditionals, loops, etc. PHP has become popular because it is easy to learn, relatively easy to install, and it is open source so it is free. PHP must be installed on your webserver for webpages with PHP code to work.
MYSQL: A powerful open source database. Many websites store their content and information in a MYSQL database and use PHP to extract this information for webpages as needed.
PHP, MYSQL and Apache (a open source webserver) are part of the "trinity" for open source webservers. You can download complete open source packages with all three of these components. Just check out the source links. These source links let you install PHP, MySQL and Apache on your personal PC to play with.
Php-Nuke is a PHP application that runs on a webserver. Note that "PHP-Nuke" is a name of a software package. The "PHP" in the name is just part of the name . . . it is named after the programming language that it is written in. PHP-Nuke is a simple but powerful CMS. It is just a bunch of code that you copy onto the webserver. As you browse a page of the copied code, the webserver automatically runs the piece of PHP code that is associated with that particular webpage. This is how PHP applications work. The code is only run when a webpage is loaded. By carefully integrating many different pages with appropriate links between them, one can create a whole application of interlinked PHP pages that do complimentary things. This network of webpages is how a PHP application with many different funtions works. Each function is associated with a different webpage. PHPNuke is a good example of this. PHP-Nuke helps you upload content like pictures and text, format webpages for users to see and interact with and, when users browse to the right page, it formats webpages and shows the content exactly as you configured it. All this is done "on the fly" through PHP code in the PHP application.
PHPNuke stores the web content on a database (e.g. MySQL).
CMS is a "Content Management System" A CMS makes it easy to maintain webpages and update content. Content is usually stored in a database like MYSQL. PHP lagnauge generates webpages that help you generate your webpages for users and upload your personal content into the database and format the pages. Then when users visit, PHP is used to generate the webpage that they see from the content in the database. PHP-Nuke is one example of a content management system.