In registering, tree is a recursive registry posting order or program that delivers a profundity indented posting of documents. Beginning in PC-and MS-DOS, it is found in Digital Research FlexOS, IBM/Toshiba 4690 OS,[2][dead link] PTS-DOS, FreeDOS, IBM OS/2, Microsoft Windows, and ReactOS. An adaptation for Unix and Unix-like frameworks is additionally accessible.

The tree order is much of the time utilized as a component of a specialized help trick, where the order is utilized to involve the order brief screen, while the trickster, professing to be specialized help, types extra content that should look like yield of the order.

Without any contentions, tree records the documents in the current registry. At the point when index contentions are given, tree records all the documents or catalogs found in the given registries one by one. Endless supply of posting all documents and catalogs discovered, tree restores the all out number of records and registries recorded. There are alternatives to change the characters utilized in the yield, and to utilize shading yield.

The order is accessible in MS-DOS adaptations 3.2 and later and IBM PC DOS discharges 2 and later. Computerized Research DR DOS 6.0, Itautec SISNE in addition, and Datalight ROM-DOS incorporate an execution of the tree order.

The Tree Unix utility was created by Steve Baker. The FreeDOS adaptation was created by Dave Dunfield and the ReactOS form was created by Asif Bahrainwala. Each of the three usage are authorized under the GNU General Public License.