Value Stream
A value stream includes all activities (value adding as well as non-value adding) in your organization that are required to deliver your product or service to the end customer.
With the help of the value stream you are able to describe all process steps required for the creation of your product or service, from raw material to the delivery of finished goods. With the Value Stream Map you are able to find potential sources of waste and try to eliminate those by concentrating on the value adding processes. Focus on customer needs and what your customers are willing to pay for. In the ideal state the your production is completely smoothed out and material as well as information stays in a state of continuous flow. Optimization of this state is always driven through productivity. Even when continuous flow is the ideal state, intermediate storages, work in progress or buffers are not evil and even can be a result of optimized material flow.
Push and Pull
To read the full article please go here. Push and Pull is a way in which you can optimize your production and produce according the value stream and flow principle when storages become tight or order books full. Just in time can avoid costly warehousing but gives you also a straight dependency on delivery performance from upstream processes or suppliers.
The pull principle describes the process from the customer's point of view. The order triggered by the customer pulls the components through production. With the push principle, the goods are pushed through production. The pull principle saves the storage of finished goods and thus also transport and search effort.