Hello all. First post on these forums, I wish you all good health and good biking.

I am thinking about buying a road bike. I will use it for exercise, testing myself, and possibly for some commuting. How much can road bike take? With their quickness on the road, are they pretty unable to take riding over dirt or grass? I would obviously be more careful when commuting on a road bike than a mountain bike, which I currently use. But are road bikes apt to break real easy if not on flat concrete 100% of the time? Again, the non-road would be minimal, but even sidewalks, there is about 2 miles where sidewalks would come into play, am I over judging the ruggedness of a road -bike for wishes of faster commute times? I appreciate any feedback from anybody who knows, or who commutes on a road bike. Thanks.