No shit - usually used
sarcastically, as in, obviously
Dumb shit - dumb person
Shit happens - bad stuff happens.
Bullshit - when someone says 'Bullshit!' it means they assume the person they're talking to is lying, bullshit means 'Lies'.
The shit - good stuff.
Shit! - used in exclamation, to show surprise,
disappointment, anger, disbelief, you get the drift.
Jackshit - don't know how to define it. But when someone says 'you don't know jackshit' it means the person doesn't know anything.
Shit - it can mean stuff. In the most literal way I can think of that is used today, it means excretions and stuff. Poo. Crap. Whatever you call it.