The SHA-1 (Secure Hash Algorithm) hash generator is used to converts the normal string to a SHA-1 hash which is a 160 bit cryptographic hash function created by the NSA in 1995. Normally it creates a 40 byte hash string for the input.

SHA-1 is mostly used to verify that a file has been unmodified. The checksum file is produced and has been transmitted, and then again once it reaches its destination.