Public transportation in Rome

There are two metro lines (a third under construction). Fare is 1 euro at the moment for bus and metro within the city limits.

There are also trains between suburbs and nearby towns, fares range for this mode.

If you want to go about only in the centre and around the main sites the metro and buses are relatively convenient, however if youw ant to stray a bit further outside the heart of the city then public transportation gets a bit more inconvenient, this is mainly because of the way Rome is built, no straight roads and several circular roads, and its so old that I don't think they are ever going to be able to make it better, at least not in the centre.

I live here and so the best way to get about is on scooter. But as a tourist public transportation is not bad and connects most of the main sites. (Most of these sites are even within walking distance if you feel like experiencing the city on foot.

Yes public transportation is quite safe.