Python’s Built-In Exceptions

BaseException

The base class for all built-in exceptions.

Exception

All built-in, non-system-exiting exceptions are derived from this class.

All user-defined exceptions should also be derived from this class.

StandardError

The base class for all built-in exceptions except StopIteration, GeneratorExit, KeyboardInterrupt and SystemExit. StandardError itself is derived fromException.

ArithmeticError

The base class for those built-in exceptions that are raised for various arithmetic errors: OverflowError, ZeroDivisionError, FloatingPointError

LookupError

The base class for the exceptions that are raised when a key or index used on a mapping or sequence is invalid: IndexError, KeyError.

This can be raised directly by sys.setdefaultencoding()

EnvironmentError

The base class for exceptions that can occur outside the Python system:
IOError, OSError.

AssertionError

Raised when an assert statement fails.

AttributeError

Raised when an attribute reference or assignment fails.

EOFError

Raised when one of the built-in functions (input() or raw_input()) hits an end-of-file condition (EOF) without reading any data.

FloatingPointError

Raised when a floating point operation fails.

GeneratorExit

Raise when a generator’s close() method is called.

It directly inherits from Exception instead of StandardError since it is technically not an error.

Also Read: Python Interview Questions on Data Types and Their in-built Functions