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There's no native way as far as I know that you can keep history of actions taken. It would take a huge amount of memory or disk space too.
But in the History palette options you can find in the options an option entitled (Automatically Create New Snapshot When Saving); This makes Photoshop create a snapshot each time you save the file. The time of day that a snapshot is created is listed next to the snapshot thumbnail. However, don't forget that all history snapshots are deleted when you close your document.
