Tree

A Tree is a connected (there is a path between every vertices) and acyclic graph. If one edge is added to the tree, it will form a cycle and if one edge is removed from the tree, it will become disconnected.

A Tree has (only one) designated root node and has child nodes. A leaf node has no child.

In a binary tree, nodes have at most two children. A perfect binary tree of n levels has 2^k-1 nodes.

Resources

https://www.youtube.com/watch?v=oSWTXtMglKE