What is a Python palindrome?

A palindrome is a string that reads the same forwards and backwards. In Python, you can check for a palindrome by comparing the string to its reverse: s == s[::-1]. For example, "radar" and "level" are palindromes, while "python" is not. When checking, you might want to ignore case and non‑alphanumeric characters: ''.join(c.lower() for c in s if c.isalnum()) == ''.join(c.lower() for c in s if c.isalnum())[::-1]. This approach runs in O(n) time and O(n) space due to the reverse operation. Palindromes are useful in problems involving symmetry, such as finding the longest palindromic substring or validating user input in certain applications.