A 'ValueError' occurs when a function receives an argument of the right type but inappropriate value. Check your inputs and ensure they meet the expected criteria for the function being called.

The 'ValueError' is a common exception in Python that occurs when a function receives an argument that has the correct type but an inappropriate value. For instance, passing a negative number to a function that expects a positive integer, or attempting to convert a non-numeric string into an integer will trigger a ValueError. To address this issue, begin by examining the error message and traceback to pinpoint the line of code where the exception was raised. Understanding the expected value for the function in question is critical; consult the function's documentation to verify what values are permissible. You can implement input validation to check the values before they are passed to the function, ensuring they meet the expected criteria. Additionally, consider using try-except blocks to catch ValueErrors gracefully, allowing your program to handle invalid inputs without crashing. By being proactive about validating inputs and understanding the causes of ValueErrors, you can enhance the robustness of your Python applications and improve the user experience.