The back-end of an application is the part that is not visible to the user. This often takes the form of a dashboard, in which administrators can, for example, make changes and add new data. The back-end part of an application supports the front-end (what the user actually sees) and usually allows the front-end to communicate with other programs and applications. The back-end environment uses a login system, often with different (access) rights for different administrators.

In general, the back-end consists of three parts: the database, the server, and the application. The application receives data from the front end and stores it in a database: a large collection of data that runs on a server. The data can be retrieved by the application from this server at later times.

Examples of processes that take place in the back-end are registering new users, uploading files, and reading news messages from a database. Back-end development covers a very broad area: from the implementation of payment methods in a webshop to the operation of a complete management system.