what does the sum of the digits of the number mean code example

Example: sum of digits

num = [int(d) for d in input("Enter the Number:")]
sum = 0
for i in range(0, len(num)):
    sum = sum + num[i]

print("Sum of Digits of a Number: {}".format(sum))

# This code is contributed by Shubhanshu Arya (Prepinsta Placement Cell Student)