Several electronic layers exist in the most documents, a fack overlooked by many writers. Probing these sublayers often reveals information non intended for release by the author. Documents in electronic formats create a "palimpsest" that even semiskilled investigators can probe for sensitive data. Palimpsest seems like an exotic work. But literally, it means "scraped again" from Greek word roots. In ancient and medieval Europe, writers often scraped off previous writing on a manyscript and wrote new text. (Writing media were in short supply and were expensive.) With modern forensic techniques like ultraviolet light and photography researchers uncover the original layer of writing. Using computer forensic techniques, thenty-first century sleuths discover text and data in electronic documents thought erased by previous users. Modern elecronic media are inherently palimpsestuous. Secrets become visible through metadata in documents, slack space in files, magnetic remanence, and other thorny ironies of information retention. They disclose information ofthe, under the radata, by unintentionally making sensitive information Web-facing or not encrypting data on a laptop, which results in information leakage.