# 21. Hashing II

- [21.1 Hash Table Recap, Default Hash Function](/cs61b-textbook-fall-2025/21.-hashing-ii/21.1-hash-table-recap-default-hash-function.md): "The whole point is that we have a bunch of lists that are all short." - Professor Hug.
- [21.2 Distribution By Other Hash Functions](/cs61b-textbook-fall-2025/21.-hashing-ii/21.2-distribution-by-other-hash-functions.md): HashMaps/Tables have fast lookup times, but behind that "superpower" is a hash function.
- [21.3 Contains & Duplicate Items](/cs61b-textbook-fall-2025/21.-hashing-ii/21.3-contains-and-duplicate-items.md)
- [21.4 Mutable vs. Immutable Types](/cs61b-textbook-fall-2025/21.-hashing-ii/21.4-mutable-vs.-immutable-types.md)