Trees (including binary trees): Know that a tree is a connected, undirected graph with no cycles. Note that a tree does not have to have a root. Know that a rooted tree is a tree in which one vertex has been designated as the root. A rooted tree has parent-child relationships between nodes. The root is the only node with no parent and all other nodes are descendants of the root. Know that a binary tree is a rooted tree in which each node has at most two children. A common application of a binary tree is as a binary search tree. Be familiar with typical uses for rooted trees.

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Trees (including binary trees): Know that a tree is a connected, undirected graph with no cycles. Note that a tree does not have to have a root. Know that a rooted tree is a tree in which one vertex has been designated as the root. A rooted tree has parent-child relationships between nodes. The root is the only node with no parent and all other nodes are descendants of the root. Know that a binary tree is a rooted tree in which each node has at most two children. A common application of a binary tree is as a binary search tree. Be familiar with typical uses for rooted trees

• This point belongs to Trees, especially Trees (including binary trees).
• You need to be able to trees (including binary trees): Know that a tree is a connected, undirected graph with no cycles. Note that a tree does not have to have a root. Know that a rooted tree is a tree in which one vertex has been designated as the root. A rooted tree has parent-child relationships between nodes. The root is the only node with no parent and all other nodes are descendants of the root. Know that a binary tree is a rooted tree in which each node has at most two children. A common application of a binary tree is as a binary search tree. Be familiar with typical uses for rooted trees.
• Use the linked flashcards and practice questions to check recall, then practise applying the idea in an exam-style answer.