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 # Plan9 tree util
 
+`tree` is written with Plan9 Operating System in mind so it may not work
+with other systems.
+
+It is using [Plan9 C compiler](https://plan9.io/sys/doc/compiler.html).
+
+## Description
+
+Tree is a recursive directory listing program that displays files in a 
+hierarchical structure with indentation based on their depth. The program 
+outputs the listing to the terminal.
+
+If no arguments are provided, tree lists all the files in the current 
+directory. When directory arguments are given, tree lists all the files and 
+directories found within each specified directory.
+