A map document is containing the layout for a map to be distributed or printed. The document is saved as an .mxd file type.
The document contains data frames, text boxes, static or dynamic texts, legends, north arrows etc.
The data frames contains the displayed geographical data symbolized as lines, points, symbols and labels. The data storage for the displayed data can be files on a disk or from one or more geodatabases.

Open a new map document

To create a new map document, open the File menu and select New… to open the New Document dialog.
Under My Templates there will be one template named Blank Map.
Under Standard Page Sizes > ISO (A) Page Sizes several templates can be found. For instance, select ISO A3 Landscape and click OK to close the New Document dialog.
The document will be opened with one data frame named Layers in the Table Of Contents.
The new map document can be saved first time to the disk by File > Save. Browse to the correct folder and specify a name for the map document and click Save. The file type will be .mxd.

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