Biztalk Pipeline Question:

A host is a logical representation of a Microsoft Windows process that executes BizTalk Server artifacts such as send ports and orchestrations. A host instance is the physical representation of a host on a specific server. A host can be either an in-process host, which means it is owned and managed by BizTalk Server, or an isolated host, which means that the BizTalk Server code is running in a process that is not controlled by BizTalk Server. A good example of an isolated host is Internet Information Services (IIS), which hosts the receive functionality of the HTTP and SOAP adapters. Hosts are defined for an entire BizTalk Server group; a collection of BizTalk Servers that share configuration, MessageBoxes, ports, and so on.