Python is an interpreted, general-purpose high-level programming language whose design philosophy emphasizes code readability.
Adapted from the SO Python tag wiki.
Python is a dynamically and strongly typed programming language, used for developing a wide range of applications. The philosophy of Python is succinctly formulated in The Zen of Python (Author: Tim Peters), which can be revealed by issuing this command at the interactive interpreter:
>>> import this
The exhaustive and up-to-date reference to the Python specification and standard library documentation can be found in the official docs. There are a wide variety of implementations, which have relevant Stack Overflow tags reserved for them, although for most questions the python tag should be sufficient. The reference implementation is known as CPython.