[Tutor] can someone explain to me how this works

[Conrad Koziol]

Hey thanks for the tips !!!

def compare(a,b):
         if a[1]>b[1]: return 0
         else: return -1

i tried this out and it works, but i dont understand the logic behind it
:(
can someone help me out

i also dont get how it compares all the tuples in a list. Dont you need to enter
in two values not just one list?????