軟體保護中，把不能複製的標記或簽名存放在軟碟上的方法，用一個特殊測試程式來檢測簽名是否存在，如不存在，則被保護的程式不能運行。In software protection, a method of giving a mark, or signature, that cannot be duplicated, to a floppy disk. A special test routine detects if a signature is present, and if it is not found the protected program will be disabled.