Production Systems

1. Push type: Release of work is based upon the demand forecast. This type is less responsive to demand fluctuations as it is based on long term forecasts.

2. Pull type: Release of work is based on system status. This type is more responsive as production is done based on the actual demand. Example: items kept in a shelf in the supermarket.

3. Hybrid type: It is a combination of both push and pull type. For example in case of Dell they forecast the component parts demand and release order for production (push type) but assembly of final product is done only when there is an order for it (pull type).

Of all the three systems Hybrid type will have least customer lead time assuming all three work in the same production system.

Manufacturing Environments

1. Make to stock: Final product is made to stock. Customer lead times are small in this case. Example: FMCG products.

2. Assemble to order: There is no finished goods inventory, assembly of product is done once the order is placed. Customer lead times higher than in make to stock.
Example: ordering laptops from Dell

3. Make to order: Drawing and design of standard parts are used and customization of product is done based on the customer requirement. Customer lead time is higher compared to make to order and assemble to order.

4. Engineer to order: In this case the whole product is designed and manufactured from scratch. Intensive interaction with customer and lead time is highest.

Operations Planning and Control

OPC is concerned with planned transformation of inputs into desired outputs.
Aim of OPC is to provide goods and services in right quantities, place, time, quality and cost.