InfoPath can be used in several ways. Each approach results in the creation of XML documents that, in turn, can be submitted to various appropriate types of data store. An InfoPath form can be created without a data source; since that practice is likely to be of use only in prototyping, however, it isn't described in detail here.
Using W3C XML Schema
A W3C XML Schema schema document can be used as a data source. That schema document defines the structure of the XML that the InfoPath form will produce. Validity constraints in the schema document are enforced by InfoPath; invalid forms cannot be submitted, ensuring that only complete and valid data is collected.
If necessary, forms can be saved locally; for example, to allow missing or invalid data to be checked and corrected before submission.
Using Source XML Document
Creating an XML source document can be useful for prototyping an InfoPath form template. InfoPath creates a simple W3C XML Schema schema automatically from the XML document.
Interacting with XML Web Services
InfoPath can connect to XML web services, providing a route to corporate business processes. The InfoPath form can be specified to receive data from a web service, to submit data to a web service, or both. One limitation of XML web services support in InfoPath 2003 is that inline schemas are not supported.
Interacting with Microsoft Access
Connecting to a Microsoft Access database is very easy, by means of a wizard. This strategy allows a data source to be chosen and relevant fields from selected tables to be mapped to InfoPath's data schema. Typically, both query view and data view are part of the form template used to connect to a Microsoft Access database; I'll show an example later in this article.
Interacting with SQL Server 2000
Connecting to a SQL Server 2000 database is a further wizard option, with choices similar to those for Access databases.
Publishing to Windows SharePoint Sites
InfoPath form templates can be published on Windows SharePoint Services (WSS) web sites or to SharePoint Portal Server 2003. WSS is the successor to SharePoint Team Services and is an add-on to Windows Server 2003. InfoPath form data can be displayed as columns in a WSS form library.