In software architecture, the end-user-facing layer of a piece of software, including design, navigation, text and imagery—overall, an interface to interact with. In CMS terms, the frontend stands for the client-facing parts of the system, as opposed to the data and content administration. The frontend is often referred to as the presentation layer, which displays the content stored in the data access layer.
Sitefinity was built for light, mobile-first presentations with full Bootstrap support, while its decoupled architecture lets you leverage multiple frontend technologies.