Remainder advertising (also known as remnant or last minute advertising) refers to the advertising space that a media company has been unable to sell. Depending on the medium, it could be ad space or time. Often it can be bought at a steep discount. Advertising time and space is a perishable commodity. If it is not sold, it is lost, used for a "house ad", or given away for public service announcements or some other non-revenue producing filler. However, instead of taking a loss for unsold airtime or ad space, media outlets will often take far less than their usual retail fees to unload their remnant space. This means advertisers can buy what is typically expensive media for a great deal less money than normal. Although the space and/or time is sold at a steeply discounted rate, media selle