Inventory is a popular and important term in business and refers to a stock or a list of items. This stock or property can be used to refer to property, goods or other things. in terms of online advertising, the term inventory is generally used to refer to the advertising space or stock that is available with the publisher or with the online media company. This advertising inventory is meant to be sold to the advertiser so that he may use it promote his own website.
The online media companies act as intermediate between the advertiser and the publisher. He acknowledges the publishers who wish to sell a section of their website page to advertisers who may want traffic from their. The media company then maintains an inventory of the available advertising space ad sells it to the advertisers so that they may promote their brand through. The good spaces which can get them better traffic are generally sold through a bidding system. The inventory that is left with the online media company is then referred to as remnant inventory and is sold at a discounted price. Thus the online businesses also maintain their inventory to keep a track of the available stock.