Error Handling

When writing code, it’s common to encounter errors. Some errors stop the program from running — these are known as exceptions. Python gives us tools to manage these errors gracefully without crashing the program.

What is an Exception?

An exception is an error that occurs during the execution of a program. For example:

Common Built-in Exceptions

Here are a few common exceptions:

To handle exceptions, use try-except. This allows your program to continue running even if an error occurs.

Using else with try-except

You can add an else block to run code if no exception occurs.

Using finally

The finally block always runs, whether there is an exception or not. It’s useful for cleanup.

Raising Your Own Errors

Sometimes, you may want to create errors on purpose using the raise keyword.

Why Use Error Handling?

• Prevent program crashes
• Display user-friendly messages
• Handle expected or unexpected inputs safely
• Maintain control of the program’s flow

Summary

• Use try to test code that may cause an error.
• Use except to handle specific errors.
• Use else if no error occurs.
• Use finally to execute code no matter what.
• Use raise to throw your own exceptions if needed.