History panel»

The History panel Window > Panels > History records all operations you perform with glyph contours, glyph metrics, kerning or glyph info.

The History panel displays the list of operations and a few buttons:

Operations on the blue background are applied operations. Those on the white background were undone. Click on Undo & Redo buttons below the list to roll back and forward or simply click on the particular line.

Button Operation
Record Takes a snapshot of the current glyph outlines and remembers it in memory for further interpolation
Rewind Interpolates back to the remembered snapshot
Fast Forward Interpolates from the snapshot (taken with Record) to the current glyph outlines
Undo Cancels the last operation on the blue background
Redo Performs the first operation on the white background

For information on using Record, Rewind, Fast Forward (Tools > Rewind menu) see the Rewind Record article.