What keeps draining my car battery?

What keeps draining my car battery?
#1 Electrical Problems
#2 Keeping the headlights on
#3 Weak Condition of the Battery
#4 Loose Battery Connections
#5 Parasitic Drain
#6 Faulty Charging System
#7 Old Battery
#8 Driving in many short distances
#9 The battery isn’t charging while driving