The SHA-256 (Secure Hash Algorithm 256) algorithm generates an unique 256 bit (32 byte) signature for a text. The cryptographic hash algorithms produce irreversible and unique hashes.
SHA-256 is the successor hash functions to SHA-1, and is one of the strongest hash function in SHA family.
We can easily decrypt SHA-256 algorithm using new hardware (GPU or CPU), so it is not recommended to use this SHA256 string for password.