How to verify the integrity of a Linux distribution iso image -

When we decide to install an operating system based on the Linux kernel, the first thing we do is to download its installation image, or ISO, from the official distribution website. Before proceeding with the actual installation, however, it is crucial to verify the integrity of the image, to be sure it is what it claims to be, and nobody has compromised it.

This is a companion discussion topic for the original entry at

Personally I use Transmission, which verifies the download when done downloading and then verify again with GtkHash.
I have not had any problems, since dial up days!