A map template is a map document (.mxd) from which new documents can be created. Templates may contain basemap layers or be a variety of commonly used page layouts. Map templates make it easy to reuse or standardize a layout on a series of maps. Using a template can save you time, since you don't have to manually reproduce the common parts of the maps. Like maps and layers, templates can be shared within an organization to increase productivity and standardize the maps that the organization produces.
To share customizations on your user interface, see Fundamentals of saving your customizations.
Creating a new map template
Any map document (.mxd) can be used as a map template. To create a new template, simply save or copy the map document into a special folder in your user profile. This will create a template that only you can see. You can also add user-defined categories (folders) to organize templates within the special folder. Copy the map document templates and folders to the following location:
%APPDATA%\ESRI\Desktop<release number>\ArcMap\Templates
Alternatively, you can create templates for all users of the system listed under the Templates node under New Maps. By default, system templates are located in the ArcGIS installation directory; however, the ArcMapAdvancedSettings.exe can be used to change the default location. This application is located in the Utilities folder of your ArcGIS installation directory. System templates are initially located in the following location by default:
<install drive>:\Program Files\ArcGIS\Desktop<release number>\MapTemplates
New categories for templates are made available by creating folders beneath the templates folder locations. Categories will only appear in the Getting Started, New Map, and Change Layout dialog boxes if a map document is present in the folder under the Templates or My Templates locations.
Selecting a template in the Getting Started dialog box
When you create a new document from a template, an untitled map is opened based on the selected template. These templates are listed under the My Templates node under New Maps.
The Select Template dialog box
User and system templates are also available when changing your page layout in the Select Template dialog box. New templates are available in the Select Template dialog box from the same user profile and system location used by the Getting Started dialog box.
To open the Select Template dialog box, click the Change Layout button 
on the Layout toolbar.
Converting existing map templates (.mxt files) to map documents
To convert your .mxt files, open the file from the Catalog window as an untitled map document and save it to the file system.