A standard purchase order (PO) is created when the details of the required goods or services are known. Same as other purchase orders, this one is also a one-off procurement that has the complete set of specifications such as price and quantity with clearly defined payment and delivery timelines as well as location.
For example, an office raises a standard purchase order when it intends to buy a few desks and chairs in the same configuration. This could be a one-off purchase where the contract would be closed once the goods are delivered to the office in perfect condition.
Apart from standard purchase order, other types of purchase orders are: