# tree (10-tree.org)

A tree is a plant with a woody trunk and branches. People also use the word for family trees, which show parents and children across generations, or for any branching diagram that splits into smaller parts.

## What a model may hear
- binary search tree (computer science, algorithms): assume a hierarchical data structure with nodes and child pointers, used for fast lookup and sorting
- directory tree (file systems, operating systems): treat the word as a folder hierarchy, with root directory, subdirectories, and files as leaves
- decision tree (machine learning, statistics): expect a flowchart-like model for classification or regression, with splits on feature values
- parse tree (compilers, linguistics): look for a syntactic structure showing how a sentence or expression decomposes into constituents
- spanning tree (networking, graph theory): think of a subset of edges connecting all nodes in a graph without cycles, as in the Spanning Tree Protocol

## Where people and models part ways
- Says: "Draw my family tree"
  Means: a diagram of relatives and ancestors
  May be taken as: generate code for a binary tree data structure or a phylogenetic tree algorithm
  Say instead: "Draw a diagram showing my family members and how they are related, like a chart with parents and children"
- Says: "Find the root of the problem"
  Means: the original cause
  May be taken as: discuss tree root nodes in data structures or DNS root servers
  Say instead: "Find the original cause of the problem"
- Says: "The tree has many leaves"
  Means: foliage on a plant
  May be taken as: describe terminal nodes in a data structure or end nodes in a network
  Say instead: "The plant has many leaves"
- Says: "Balance the tree"
  Means: even out a diagram or structure visually
  May be taken as: apply self-balancing tree algorithms like AVL or red-black tree rotations
  Say instead: "Make the diagram look evenly spaced on both sides"

## Tips
- Say 'plant' or 'wood' if you mean the living thing, not 'tree'
- Say 'folder structure' or 'file hierarchy' instead of 'tree' for directories
- Say 'chart' or 'diagram' instead of 'tree' for family or organizational visuals
- Add 'data structure' only if you want the technical kind
- Say 'decision flowchart' if you want a branching choice model without machine learning assumptions

## Often confused with
- graph: any connections, not necessarily hierarchical
- heap: a tree with ordering by priority, not shape alone
- trie: a tree for string prefixes, pronounced the same
- forest: multiple disconnected trees in graph theory
- DAG: directed acyclic graph, allows shared children
- list: linear, not branching