AWT (Abstract Window Toolkit) is the original Java GUI toolkit. It is part of the Java Foundation Classes (JFC) — the standard API for providing a graphical user interface (GUI) for a Java program. Swing is a part of JFC that provides a set of "lightweight" (all-Java language) components that, to the maximum degree possible, work the same on all platforms. Swing components are used to create graphical user interfaces for Java applications.