If you are on OS X then BBEdit will do this for you.

On 4/23/13 3:24 PM, "Wilhelmina Randtke" <[log in to unmask]> wrote:

>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