How to convert a text file's line termination from Windows/DOS to Unix? [duplicate]

How to convert a text file's line termination from Windows/DOS to Unix? [duplicate]

I have several scripts that produce a /bin/sh^M bad interpreter error message when they are run. I believe this is because they are formatted with the Windows/DOS line termination instead of the line termination expected by Unix/Linux (Ubuntu 9.04 for an embedded system in my case).