> ## Documentation Index
> Fetch the complete documentation index at: https://docs.abbyy.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Data source properties

> Specify a service field's data source on the Data Source tab: pick the source, name a document or batch registration parameter, and choose the data type.

On the Data Source tab, the source and the data type of the service field are specified:

1. From the Source list, choose a data source for the field.
2. If you select Document registration parameter or Batch registration parameter, specify the name of the registration property to be used as a data source in the **Parameter Name:** field.
3. For **Data Type**, select the data type of the service field.