How does one distinguish between an error and an unforced error?

That's a tennis term, not a baseball term. There's no such thing as an unforced error in baseball, because every error is unforced.

edit: An example of an unforced error in tennis would be hitting what should be an easy shot into the net.

Is there a difference between the two. What is a forced error then...should a forced error even be considered an error?....i mean if you're forced to get it, thats fair for the fielder.

I've never heard of the term unforced error in baseball, but I have heard of it in basketball, when players have unforced turnovers...such as dribbling the ball off their foot. A regular turnover would be a defender sneaking up behind the ball-handler and poking it away. Two differences there.

In baseball, I think an error and an unforced error are the same since baseball really is 9 on 9 game. Its more of a 1(batter) v. 9(fielders).

EDIT: I mean the guy with the ball dribbling, if the defender takes the ball away from him, that thats an unforced error oon the guy dribbling the ball because he didnt see it coming. IN basketball, its called an unforced turnover.