CRM, CRMplus or ERP: Whats the difference between them and which one do you need?

Quite a few people struggle to understand the differences between Customer Relationship Management (CRM) and Enterprise Resource Planning (ERP) systems as some of the capabilities exist within both systems. Both CRM and ERP systems have CRM capabilities, they can handle company and contact information, track opportunities, notes and store lots of details about orders.

However if you look at w ho uses CRM or ERP systems things start to become a little clearer