Ok there is a big difference between ERP's and CRM's.
ERP: ENTERPRISE RESOURCE PLANNING:
An ERP solution is fully integrated software that allows communication across all areas of the business. ERP software applications can be used to manage product planning, parts purchasing, inventories, interacting with suppliers, providing customer service, and tracking orders. ERP can also include application modules for the finance and human resources aspects of a business.
An ERP solution can include CRM This is part of the Customer Service Module however it is tied into other modules.
It is ONE software handling multiple processes and automatically updating each stage of a job. Ie say an order comes in through sales (CRM) ordering to buy 10 pairs of pants, this will then check in the ERP Warehouse module to make sure this item is available, if not it will then work through to the manufacturing module which will then create an alert for them to make some more pants, it will then update dispatch send it to the customer, update Finance and send an invoice and then finally update the CRM for future customer interaction.
CRM :CUSTOMER RELATIONSHIP MANAGEMENT:
A CRM solution is software designed to manage all customer interactions in an organised way. It allows management, salespeople, people providing service, and perhaps the customer directly could access information, match customer needs with product plans and offerings, remind customers of service requirements, know what other products a customer had purchased, and so forth.