Which American code should be used?

Any body please tell me that which american code is to be used for the design of the steel industrial shed.

AISC ASD

AISC LRFD

AISC 360-05.

also, what are the differences between these codes.

i am going through to a problem, that when i used AISC ASD my structure gets failed, but when i use the AISC LRFD the structure gets designed.So, i want to know why this happens.