md5sum — Compute and Check MD5 Check sums.
Summary:
md5sum computes a 128-bit checksum/fingerprint/message-digest for each specified file. md5sum can also determine whether a file & checksum are consistent.
Example:
$ md5sum file — Compute and print the MD5 checksum of that file.
$ md5sum -c input.txt — Read checksum and filename from the file and validate checksums.
$ md5sum -w -c input.txt — Same as above and warn if the checksums format is wrong in the file.
$ md5sum –status -c input.txt — Indicate the status in exit status code.
Read: man md5sum