UFT is an advanced version of HP's QuickTest Professional (QTP) automation testing tool that supports both GUI and API testing. Some key improvements in UFT over QTP include support for additional browsers, operating systems, and programming languages. UFT also features faster installation, a unified interface for GUI and API testing, improved debugging tools, and the ability to run specific steps or functions during API testing. Overall, UFT provides a more robust and efficient platform for functional and regression testing compared to QTP.