In the most general terms, a Web application is a piece of software that runs on a Web server. A Web server is just a specialized computer designed to host and deliver Web pages.
Many Web applications are comprised of two components: files and a database. When installing a Web application, it is necessiary to make sure all files are copied over into the appropriate location AND that a database (and database user) has been set up to connect to those files. Often, some configuration is required to make sure the application knows how to access the database.
The system we use for Bergbuilds relies upon a special script installer called Installatron (it's in the cPanel) that automates installation for dozens of open-source applications. When using Installatron, folks don’t need to worry about moving files, creating databases, or doing most initial configurations. It’s just handled. Learn more about Installatron here. This is one of the major reasons why we are excited to partner with Reclaim Hosting to provide Domains for the Muhlenberg community.
In order to run on the Bergbuilds.domains server, Web applications must be able to run on a LAMP server, which is the particular kind of Web server that we use (LAMP is an acronym of Linux, Apache, MySQL, and PHP. Here's a short Lynda.com video providing more background, if desired).