'IndexError' occurs when trying to access an index that is out of range in a list or other indexable object. Always check the length of the list before accessing an index to avoid this error.

'IndexError' is a common exception that arises in Python when you attempt to access an index that is out of the valid range for a list, tuple, or other indexable objects. This can happen if you mistakenly reference an index that is greater than or equal to the length of the object or a negative index that exceeds the object's size. To prevent IndexErrors, always verify the length of the list before accessing an index using the len() function. For example, if you want to access the third item in a list, ensure the list contains at least three items. You can also implement exception handling using a try-except block to catch the IndexError and handle it gracefully, perhaps by providing a default value or logging an error message. Additionally, when iterating over lists, consider using a loop that directly iterates through the elements rather than relying on index values. By being mindful of index usage and incorporating checks, you can avoid IndexErrors in your Python code.