Compact cranks?

[Aramis7]

I'm a bit confused by the compact cranks (50-34 teeth). Do you also need a compact casette to match?. OR they are used stand-alone?

Whats the main advantage of compacts?

Thanks

[RapDaddyo]

I use an FSA compact crank with Campy cassettes and it works fine with my derailleurs and all of my cassettes. I switched to the compact cranks to get more options at the low end because my cadence was lower than I prefer on some grades. Personally, I like my drivetrain options with the compact cranks, using different cassettes depending on the course.

[PeterF]

I'm a bit confused by the compact cranks (50-34 teeth). Do you also need a compact casette to match?. OR they are used stand-alone?

Whats the main advantage of compacts?

Thanks
The idea behind them is to give you a better range with a standard cassette. without having to go with a triple set-up. There is nothing else needed with them (provided your bottom bracket has the right spindle), although some companies offer a front derailleur made for the compact crank. I understand a regular front derailleur works fine too.