Three packages comprise the Abstract Window Toolkit: java.awt, java.awt.image, and java.awt.peer.
AWT Package
The java.awt package provides GUI elements used to get input from and display information to the user such as windows, buttons, scrollbars, and text items.
AWT Image Package
The java.awt.image package contains classes and interfaces for managing image data, such as setting the color model, cropping, color filtering, setting pixel values, and grabbing snapshots of the screen.
AWT Peer Package
The java.awt.peer package contains classes and interfaces that connect platform-independent AWT components to their platform-dependent implementation (such as Motif widgets or Microsoft Windows controls).