What is an operational layer?
Operational layers are the layers with which your users will interact in the field. They contain the features that are most important to your organization, such as infrastructure for a local government, network assets for a utility, or wildlife observations for an environmental agency. You can find and use a suitable operational layer that's already available on ArcGIS Online, but if your organization has collected extensive data about its infrastructure, you'll want to build an operational layer from your geographic information system (GIS) data.
Operational layers can be queried and edited. Operational layers for display and query are defined from a map service. Operational layers for editing feature are defined from a feature service. You can use one or several operational layers in your web map.
Types of operational layers include feature layers and time-aware layers. For more information on operational layers, see the following topics:
How to add a dynamic map service layer
How to add a local dynamic map service
How to add a feature layer from an online service