One may not use all of the tools/applications mentioned in this article on daily basis, but these are some of the widely used applications in Linux administration and related Linux jobs.
The acronym LAMP refers to a solution stack of software, usually free and open source software (Linux, Apache, MySQL and Perl/Python/PHP), used to run dynamic Web sites or servers.
In the proprietary closed source model, the entire development cycle evolves within a single company. Programmers write code, hide it behind binaries and charge the customers to use the software. No one ever gets to know how bad the software really is!