A Stock Movement transaction adjusts the Level (quantity), Value or Location of Stock in a traceable fashion.
Generally, Stock Levels are increased by Goods Inwards and Reduced by Picking, but in the real world stock quantities vary for a variety of reasons and need to be corrected.
The Stock Movement facility creates a serial number for each transaction, records the adjustment figures, classifies them, records a narrative, an authorisation and implements the changes with an authorisation date.