LAMP refers to a stack of web technologies based on Linux, Apache, MySQL, and PHP/Perl/Python.
LAMP, (Linux, Apache, MySQL and PHP/Perl/Python), is an acronym for a solution stack of free, open source software, referring to the first letters of: Linux (operating system), Apache HTTP Server, MySQL (database software) and PHP (or sometimes Perl or Python), principal components to build a viable general purpose web server.