An offensive term used to describe pikeys or scallys.
It can also be a sarcastically affectionate term used to talk to friends by replacing "mate" with "bart", when greeting them.
("Hello my friend/mate how is life treating you?")
"Look here come some barts"
("Some pikeys are coming towards us)
Barting is in no way pleasureful but could be very amusing to people nearby who recognise the distinguished sound.
Trains under and above ground in the SF bay area. They even go UNDER THE BAY.
Sort of ridic expensive.
A lot of people depend on them so when they strike or break down, everyone's fucked.
Michelle: We can't all fit in your car though, and mine's in the shop!
Monique: I know, we'll take BART!