Compound lifts are lifts which used multiple-joints e.g Squats, Deadlifts, Bench Press, Overhead Press, Chinups and Upright Rows
As opposed to isolation which isolate a certain joint e.g Dumbell curl, Leg curl, Tricep kickback.
Compounds are better overall because the body works as a single unit and more muscle mass is utilized because you can lift more weight with compound exercises.
Compounds will develop your whole body, its better to do 85-90% of your workout using these exercises then finish of with some isolation work.
IcE