WHAT TO LEARN FIRST
INVENTORY 
It indicates the number of FLOW UNITS in the process at a given moment in time.
FLOW RATE
It can also be called throughput and identify the number of UNITS going through the process per UNIT OF TIME.
FLOW TIME 
It indicates how much TIME it takes a UNIT to go from the beginning to the end of the process.
BOTTLENECK
It expresses the “PROCESS STEP” with the Lowest capacity within the whole process. It is measured in UNIT/Min or UNIT/Hour.
PROCESS ANALYSIS 
A PROCESS can be defined as “a logical series of related transactions that converts input to results or output” (Andersen).
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