History
Over the years, business models have become much more sophisticated. The bait and hook business model (also referred to as the "razor and blades business model" or the "tied products business model") was introduced in the early 20th century. This involves offering a basic product at a very low cost, often at a loss then charging compensatory recurring amounts for refills or associated products or services. Examples include: razor and blades cell phones and air time computer printers and ink cartridge refills and cameras and prints . A variant of this model is Adobe, a software developer that gives away its document reader free of charge but charges several hundred dollars for its document writer.