What is an iterable in Python?

An iterable is any object that implements the __iter__() method that returns an iterator, or that implements __getitem__() allowing indexed access. Lists, tuples, dictionaries, sets, strings, files and generators are all iterable. Iterables can be used in for loops, comprehensions, and functions such as map(), filter(), or sum(). They are fundamental in Python, allowing data sequences to be processed uniformly.