The presentation discusses splay trees and Euler tour trees. It defines a splay tree as a self-balancing binary search tree that rearranges elements recently accessed to the root through rotations. Splay trees have faster access times than other self-balancing trees like AVL and red-black trees. The presentation covers splay tree operations like search, insert, delete and the zig, zig-zag, and zig-zig splay steps. It also discusses Euler tour trees, which were invented by Euler and are used for dynamic connectivity problems by representing trees as node sequences.