[MRP] What is Master Production Schedule (MPS)?

A good article from Metalink Note:200574.1

"A schedule developed from firm orders or from forecasts of demand. The MPS is a key input into a material requirements planning (MRP) system. The MPS identifies how many of each end product need to be produced and when they need to be produced by within each planning period. This data forms one of three keyinputs enabling an MRP system to produce detailed timings for component manufacture and material purchases. It summarizes what the business plans to make and drives the operation in terms of what is assembled, what is made, and what is bought in. In addition it forms the basis for planning the utilization of labour and equipment and determines the requirements for materials and cash."

MDS serves as input for MPS, MPS serves as input for MRP. However, in simple MRP implementation, MPS some times been skipped.