You have tried to do something to a variable of the wrong type. There are many forms:
TypeError: illegal argument type for built-in operation
You asked Python to do a built-in operation on the wrong type of variable. For example, you tried to add a number to a string.
TypeError: not enough arguments; expected 1, got 0
You used a function without supplying the correct number of parameters.
TypeError: unsubscriptable object
You tried to reference a variable that did not have more than one element (e.g. a float or integer) by offset:
>>> x = 5 >>> print x