Hash concept, sha-256, and bitcoin

[DannyHamilton]

Here's a video I just watched that I felt gave an interesting introduction to the concept of a "hash function".  Perhaps this thread belongs in the "Off Topic" sub-forum, but it felt like a discussion about hashing fit into Bitcoin Discussion.

https://www.youtube.com/watch?v=SOgn6J12NWE&t=03m12s

As a bonus, the presenter mentions both sha-256 and bitcoin around the 6:40 mark.