Pragmatic Unicode: Python's Unicode Sandwich

Commenters point to it as the clearest explanation of Python's bytes versus Unicode model and the Unicode sandwich, which finally makes the confusion click.

Ned Batchelder's PyCon 2012 talk gives a quick overview of what Unicode is, then focuses on what a Python programmer needs to handle text correctly. It presents the 'Unicode sandwich' strategy: decode bytes at input, work with Unicode internally, encode at output.