Royalty-free stock photography (RF) "Free" in this context means "free of royalties (paying each time you use an image)". It does not mean the image is free to use without purchasing a license or that the image is in the public domain.

For many years, stock photography consisted largely of outtakes ("seconds") from commercial magazine assignments. By the 1980s, it had become a specialty in its own right, with photographers creating new material for the express purpose of submitting it to a stock house. Agencies attempted to become more sophisticated about following and anticipating the needs of advertisers and communicating these needs to photographers.

Using the Internet as their sole distribution method, digital technology and utilizing photographers from around the globe, these companies are able to offer stock libraries of good quality for very low prices.