Enterprise resource planning Overview

Some organizations — typically those with sufficient in-house IT skills to integrate multiple software products — choose to implement only portions of an ERP system and develop an external interface to other ERP or stand-alone systems for their other application needs. For example, one may choose to use the HRMS from one vendor, and the financials systems from another, and perform the integration between the systems themselves.

This is very common in the retail sector, where even a mid-sized retailer will have a discrete Point-of-Sale (POS) product and financials application, then a series of specialized applications to handle business requirements such as warehouse management, staff rostering, merchandising and logistics.

MRP vs. ERP

Manufacturing management systems have evolved in stages over the past 30 years from a simple means of calculating materials requirements to the automation of an entire enterprise. Around 1980, over-frequent changes in sales forecasts, entailing continual readjustments in production, as well as the unsuitability of the parameters fixed by the system, led MRP (Material Requirement Planning) to evolve into a new concept : Manufacturing Resource Planning (or MRP2) and finally the generic concept Enterprise Resource Planning (ERP)

http://en.wikipedia.org/wiki/Enterprise_Resource_Planning