WinForms
WinForms (Windows Forms) is a graphical user interface (GUI) framework for building desktop applications on the Microsoft .NET platform, primarily for Windows. It provides a set of controls, such as buttons, text boxes, and forms, that developers can drag-and-drop or programmatically arrange to create rich client applications. It is event-driven, allowing developers to handle user interactions like clicks and key presses through event handlers.
Developers should learn WinForms when building traditional, data-intensive desktop applications for Windows, such as internal business tools, utilities, or legacy system interfaces, due to its simplicity and rapid development capabilities. It is particularly useful for projects requiring a straightforward, form-based UI without the complexity of modern web or cross-platform frameworks, and it integrates well with other .NET technologies like ADO.NET for database access.