The View History / Undo option allows you to undo up to 20 operations per image, no matter how long ago you performed them. For example, say you use the Add Text feature to add your child's name to a picture. After clicking Save, you realize that you accidentally double-typed a letter. In previous versions of Images: In Context!™, this would have resulted in a loss of the original image. With new versions of Images: In Context!™, simply right click on the image, choose the Images: In Context!™ menu, and click View History / Undo. You'll be presented with thumbnails of the last 20 changes you made to your image.
To undo one or more operations, click on the thumbnail of the image snapshot you'd like to roll back to, and click the Roll Back button.
If you'd like to keep the image as is, but save a snapshot of a previous version of the image to a new file, highlight that thumbnail and click the Save As... button. You will be prompted for a location for the new image, and you can even chance the filetype when saving.
If you're satisfied with an image, and sure that you don't need to keep the history, you can click the Purge All button to purge all history and free up some hard disk space.