A purchase order is a legally binding document between a buyer and seller in which the terms of a purchase are set, including the price, quantity of items and delivery date. An online purchase order is one that is written, viewed and approved online rather than in hard copy.
Online purchase orders have several advantages over paper copies. Online orders are easy to track, since users of the online interface can use search features to find key words. Online purchase order systems also only maintain one copy of the order that is viewable by all authorized users so everyone can see the most recent version of the document.