How to add imagery basemap data from arcgis online to ArcMap

A basemap provides a background of geographical context for the content you want to display on a map. When you create a new map, you can choose which basemap you want to use. You can change the basemap of the current map at any time by using the basemap gallery or using your own layer as the basemap. You can also create a basemap containing multiple layers from the Contents pane in the map viewer.