Trees are directed acyclic graphs.
Any tree structure can be implemented using a linked memory structure - the nodes of the tree simply become objects that live in memory, and the tree structure becomes a collection of links, similar to a linked list.
A concrete implementation (in Java) of a binary tree using a link structure for memory is at Binary Trees/LinkedBinTree - link: https://git.charlesreid1.com/cs/java/src/master/trees/LinkedBinTree.java
TreesPart of Computer Science Notes
Series on Data Structures
Abstract data type: Trees/ADT
Preorder traversal: Trees/Preorder
Postorder traversal: Trees/Postorder
In-Order traversal: Binary Trees/Inorder
Breadth-First Search: BFS
Breadth-First Traversal: BFT
Depth-First Search: DFS
Depth-First Traversal: DFT
Finding Minimum in Log N Time: Tree/LogN Min Search
Abstract data type: Binary Trees/ADT
Flags · Template:TreesFlagBase · e