Whyteboard is a free painting application for Linux, Windows and Mac. It is suited towards creating visual presentations and for overlaying PDF images with annotations. Draw on a canvas using common tools: pen, rectangle, circle, and text. Annotate over PDF files. Drawn shapes can be resized, moved, rotated and re-colored. Tabbed drawing: each tab represents a whiteboard "sheet". Each sheet has unlimited undo/redo operations. Your drawing history can be replayed on a per-sheet basis. Each sheet has a thumbnail of the canvas that updates as you draw. Closed sheets can be re-opened, restoring their data. Notes, similar to Post-It Notes. A tree in a side panel gives an overview of all notes. Resize the canvas easily by dragging it around. Embed an audio/video player onto the canvas.