Tool to highlight differences in two files

From: Wilhelmina Randtke <randtke_at_nyob> Date: Tue, 23 Apr 2013 15:24:16 -0500 To: CODE4LIB_at_LISTSERV.ND.EDU

I would like to compare versions of a website scraped at different times to
see what paragraphs on a page have changed.  Does anyone here know of a
tool for holding two files side by side and noting what is the same and
what is different between the files?

It seems like any simple script to note differences in two strings of text
would work, but I don't know a tool to use.

-Wilhelmina Randtke