New to programming, loop question

[Larz60+]

the range is 0 to int(string length/2) -- stops after middle of string is reached
it then checks to see if current character (i) is equal to the character at the same distance from end

example: say word is 'civic'

Output:
length of word / 2 is 5/2 = int(2.5) = 2

range = 0 - 2
..........................................................
| Iter. | i | s[i] | len(s)-i-1 | s[len(s)-i-1] | RetVal |
..........................................................
|   1   | 0 | 'c'  | 5-0-1 = 4  | 'c'           | True   |
..........................................................
|   2   | 1 | 'i'  | 5-1-1 = 3  | 'i'           | True   |
..........................................................
s is a palindrome

if you add a 'k' ro civic ('civick')
the loop will fail on first iteration and return False.