Inventory refers to a procedure for taking stock of assets and liabilities. It is carried out on a specific deadline date for all values to enable correct bookkeeping and accounting. Four types are possible. The most common variant is the annual inventory, in which all values are recorded on a deadline date. With inventory sampling, the total quantity is determined on the basis of a representative quantity; with continuous inventory on the basis of entries and withdrawals; and with early or postponed inventory on a specific date outside the deadline date. Since values such as liabilities cannot be counted like objects, there are three different procedures. These are physical inventory (e.g. counting), book inventory and asset inventory.