Windows Forms is a graphical user interface (GUI) class library included in the Microsoft .NET Framework. It allows developers to create desktop applications for the Windows operating system using a drag-and-drop interface. This makes it easier to design forms and controls, such as buttons and text boxes, without extensive coding. Applications built with Windows Forms can handle user input, display data, and interact with other software components. It supports various controls and events, enabling developers to create responsive and user-friendly applications. Overall, Windows Forms simplifies the process of building rich desktop applications for Windows users.