why this program is giving me error

Question

#list of position holders
student=["billgates","elonmusk","jeffbezos","mark zuckerburg"]
counter=0
Max=len(student)
while counter<=Max:
print("1 "+student[counter]+"-_-")
counter+=1

Output
1 billgates-_-
1 elonmusk-_-
1 jeffbezos-_-
1 mark zuckerburg-_-

Traceback (most recent call last):
File "./Playground/file0.py", line 6, in <module>
print("1 "+student[counter]+"-_-")
IndexError: list index out of range

Answer 1

Or:

while counter < Max:

Answer 2

Length starts with 1 and index with zero.