My father found a in his garage and gave it to me, he wasn't sure
where it came from but he knows its been laying around for at least 20
years.

The plane looks like this one:

http://i23.ebayimg.com/01/i/06/50/e4/42_2.JPG (also posted abpw)

Since I have no experience with hand planes, what is this plane for, and is
it worth keeping/using?

TIA.