1. Abstract Data Structures
Binary Trees

2. Root The top node in a tree.

3. Parent A node within a tree that has nodes that branch off from it (children)
Examples:
Orlando is a parent to
Hartford and Stamford
Danbury is parent to
Greenville

4. Child A node within a tree that branches off from another (parent)
Examples:
Quincy is a child of
Stamford
Greenville is a child of
Danbury

5. Subtree The grouping of a parent and a child in a tree.
Example:

6. Leaf A node with no children within a tree.
Examples:
Nashua
Greenville
Quincy
Warwick

7. Traversal Going through each of the nodes of a tree

8. Breadth-first traversal Traversing trees in level-order, where every node on a level is visited before going to a lower level.
Example:
Orlando
Hartford
Stamford
Danbury
Nashua
Quincy
Tampa
Greenville
Warwick

9. Depth-first traversal Includes the three traversal methods in-order, preorder, and postorder

10. Inorder A type of depth-first traversal where a left subtree is processed, then the parent, and then the left subtree.
Algorithm:
Perform inorder traversal
of left subtree
Visit node
of right subtree

11. Inorder A type of depth-first traversal where a left subtree is processed, then the parent, and then the left subtree.
Example:
Danbury
Greenville
Hartford
Nashua
Orlando
Quincy
Stamford
Tampa
Warwick

12. Preorder A type of depth-first traversal where a where a node is visited before its children
Algorithm:
Visit node
Perform inorder traversal
of left subtree
of right subtree

13. Preorder A type of depth-first traversal where a where a node is visited before its children
Example:
Orlando
Hartford
Danbury
Greenville
Nashua
Stamford
Quincy
Tampa
Warwick

14. Postorder A type of depth-first traversal where a where a node is visited after its children
Algorithm:
Perform inorder traversal
of left subtree
of right subtree
Visit node

15. Postorder A type of depth-first traversal where a where a node is visited after its children
Example:
Greenville
Danbury
Nashua
Hartford
Quincy
Warwick
Tampa
Stamford
Orlando

16. Dynamic Data-Structure A data structure in which the number of elements can change during program execution