Date: Dec 6, 2012 11:33 AM
Author: ABCD
Subject: how to remove specific lines from .dat file

Hi. I have a .dat file which is similar to the following: 

abcdef 123 11aa13
jwleieo 930 39kw02
abchyt 153 83je29

and I want to give an instruction in order to remove all the lines containing the 'abc' string, which in this particular case, corresponds to the first and the third line.
How can I do this?
Thank you for your help