A basemap is the first layer that provides geographic context for your map. It serves as a blank canvas upon which you add your data to create an informative visualization.
See reference on the server-side: Basemap widget
Clicking on the Table of Content icon in the image below, the system will show the Table of Content panel. Clicking on the “Basemap” tab, the panel will show all existing basemaps. You can open each category and choose the bets one that fits your needs.
