A Stock Change is where you change the quantity of stock on hand by either “Adding” (positive value) stock or “Subtracting” (negative value) stock. So if you had Product ID “ABC” and it has a current Quantity on Hand value of 10 units in sublocation “M1″, and you do a Stock Change, “Add”(which is a Positive Number) of 10 units, the Stock level would be changed to a Quantity on Hand of 20 units.
A Stock Take is where you “Take” a physical inventory count of the stock that is physically located in the sublocation you are auditing, and the system will set the Quantity on Hand to that value that you input, and it will calculate a variance from the previous recorded stock level.
So if you had Product ID “ABC” and it has a current Quantity on Hand value of 10 units in sublocation “M1″ in the system, and you do a physical stock take, and you count the number of units truly in the location, and there are only 8, then the Stock Take would set the Stock level to be 8 units, and report a variance of -2 units. The new Quantity on hand would be 8 units.