- Mac OS X, the operating system;
- Apache, the Web server;
- MySQL, the database management system (or database server);
- P for PHP, Perl, or Python, all programming languages used for web development.
Any open source Web platform made up of these software programs and built upon Mac OS X is a MAMP.
Though originally only Apache was integrated into Mac OS X, the combination has become popular because of its low cost and because of the ubiquity of its components, and Mac OS X 10.5 and above ships with PHP and is MySQL-ready. When used in combination they represent a solution stack of technologies that support application servers. MAMP may also be used with popular CMS programs like Drupal for setting up a local development environment. 
Variants and equivalents on other platforms
With the growing use of LAMP, variations and retronyms appeared for other combinations of operating system, web server, database, and software language.
- There are a number of alternatives for different operating systems as well as a cross-platform installation known as XAMPP.
- The equivalent installation on a Microsoft Windows operating system is known as WAMP with an alternative called WIMP.
- The equivalent installation on a Linux operating system is known as LAMP.
- The equivalent installation on a Solaris operating system is known as SAMP.
- The equivalent installation on a FreeBSD operating system is known as FAMP.