C++ Builder is an integrated development environment (IDE) designed for building applications using the C++ programming language. It provides a visual design interface, allowing developers to create user interfaces by dragging and dropping components onto a form. This makes it easier to develop Windows applications quickly and efficiently. The IDE includes a powerful compiler, debugging tools, and a rich set of libraries, which help streamline the development process. C++ Builder is particularly popular for creating desktop applications, as it supports rapid application development (RAD) and offers cross-platform capabilities for targeting different operating systems.