# Connect to ESRI Map Service

ESRI Map Service data can be easily imported into ZillionInfo Online. Two options are available for this process: By Value or By Reference.

<figure><img src="/files/04Fpt8pYw0B0dgSSjk35" alt=""><figcaption></figcaption></figure>

**Import By Reference** reads the data in ESRI Map Service but do not create the data file. This data can be used as a contextual layer but cannot be used for visualization and analytics.&#x20;

For example, ESRI World Topographic Map (<https://services.arcgisonline.com/ArcGIS/rest/services/World_Topo_Map/MapServer>) can be imported by reference and be used as a base map.

**Import By Value** reads data from an ESRI Map Service and creates a data file, enabling its use for visualization and analytics. Please ensure that the data size remains manageable to avoid exceeding account storage limits.


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