There are multiple ways of using for loop in Python.
1. To iterate within a String
for letter in 'Priyaj':
   print 'Letter Present:', letter #This will print letters in the string that you iterate.
2. To iterate in an array/list
letter = ['a', 'b',  'c']
for index in range(len(letter)): #this will iterate through the element of the list/array
   print 'Current fruit :', letter[index]
3. To iterate in a range
for index in range (10,20): #this will iterate between 10 - 20
   print 'Current Number:', index 
Hope this helps.