Check MD5 and SHA1 sum for a file in Ubuntu Linux

Imagine you have a file to download with a given checksum and you want to make sure that the file is not corrupted after download.

It's really easy to compute and check the MD5 sum in Ubuntu / Linux using the terminal:

md5sum myFileToCheck

and for SHA1 checksum:

sha1sum myFileToCheck

Both commands compute the corresponding checksum of your file, so you can compare than with the original checksums.