How does Marketo differentiate between leads and contacts in Microsoft Dynamics CRM?

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      Both leads and contacts in Microsoft Dynamics CRM are called “Leads” in Marketo. We do have system managed field called “Microsoft Type” which has one of the following values.Lead: The Microsoft Type is set to “Lead” if the record in Microsoft Dynamics CRM is a Lead.Contact: The Microsoft Type is set to “Contact” if the record in Microsoft Dynamics CRM is a Contact.Empty/NULL: The Microsoft Type is empty (no value) if the record is a Marketo only record and does not have a connected record in Microsoft Dynamics CRM.