Stock images typically refer to photographs used for marketing, publishing, and presentations. There are numerous collections of stock images available online, sometimes grouped around specific themes. Vector image collections - images made for use in software programs such as Adobe Illustrator - are included in this guide as well. 

Models of stock photography include macrostock, midstock, and microstock. Macrostock is typically high-priced and exclusive, and also known as traditional stock photography. Midstock is priced between microstock and microstock. Many collections listed here are microstock companies, which is a subset of the stock photography industry. Microstock companies source their images almost exclusively online, use a wider range of content creators than traditional stock companies, and sell images at a much lower rate than traditional companies. 

Licensing 

Stock images typically have two types of licensing options: royalty-free (RF), and rights-managed (RM). Many may be in the public domain, or have a creative commons license. 

Royalty-free refers to a license where the user may make a one-time payment to use an image, and be able to use the image in several projects without needing to purchase additional licenses. RF licenses are non-exclusive. 

Rights-managed refers to licenses that allows a user to purchase a one-time use of an image for a specific purpose. Additional image uses will require additional licenses. RM licenses are exclusive. 

Please be sure to read through the licensing agreements for each collection to determine if your use is appropriate and legal.