QT, or Qt, is a popular framework used for developing cross-platform applications. It provides tools and libraries that allow developers to create software that can run on various operating systems, such as Windows, macOS, and Linux, without needing to rewrite the code for each platform. QT is particularly known for its user interface capabilities, making it easier to design visually appealing applications. The framework supports multiple programming languages, with C++ being the primary language used. QT also includes features for handling graphics, networking, and database management, making it a versatile choice for developers. Its open-source nature allows for community contributions and widespread use in both commercial and non-commercial projects.