# 20. Hashing II

- [20.1 Hash Table Recap, Default Hash Function](/cs61b-textbook/20.-hashing-ii/20.1-hash-table-recap-default-hash-function.md): "The whole point is that we have a bunch of lists that are all short." - Professor Hug.
- [20.2 Distribution By Other Hash Functions](/cs61b-textbook/20.-hashing-ii/20.2-distribution-by-other-hash-functions.md): HashMaps/Tables have fast lookup times, but behind that "superpower" is a hash function.
- [20.3 Contains & Duplicate Items](/cs61b-textbook/20.-hashing-ii/20.3-contains-and-duplicate-items.md)
- [20.4 Mutable vs. Immutable Types](/cs61b-textbook/20.-hashing-ii/20.4-mutable-vs.-immutable-types.md)