# Overview of Trees

This lesson is a quick overview of trees, their types, and some important formulas to compute the height and number of nodes in a tree.

## We'll cover the following

## Binary Trees

**Definition:** A tree having a max. of two children at each internal node

**Types:** *Perfect, Full, Complete, Skewed*

**Total number of nodes:** $2^{(h+1)}-1$

**Total number of leaf nodes:** $2^{h} or \frac{(n+1)}{2}$

**Height:** $log_{2}(n+1)-1$

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