Websters Dictionary: Forest: 3: a densegrowth of trees and underbrush covering a large tract.
Websters Dictionary: Tree: 1: a woody perennial plant having a single elongated main stem generally with few or no brahces on its lower part. 3;a, a diagram or graph that branches usually from a simple stem without forming loops or polgons.
Microsoft Press Windows 2000 Network Infrastructure Administration, Chapter 7 page 241 Introducing the Domain Name Space:... A specification for a tree-structured name space in which each branch of the tree identifies a domain and contains an information set. ...root domain at the top and multiple layers of branches stemming off of the root...
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