A **Fibonacci Heap** is a set of heap-ordered trees.
Trees are not ordered binomial trees, because

- 1.
- Children of a node are unordered
- 2.
- Deleting nodes may destroy binomial construction

Node Structure:

The field ``mark'' is True if the node has lost a child since the node became a child of another node.

The field ``degree'' contains the number of children of this node.

The structure contains a doubly-linked list of sibling nodes.