Is stock photography copyright free?
Stock photography is a collection of images that can be used for many purposes. Collections of stock photos were originally created from images taken on shoots and not used - extra material that could be used for general uses, rather than for a specific shot - for instance a shot taken to be the cover of a magazine. The images are copyrighted, either by the photographer, or by the agency controlling the images. Under the laws governing intellectual property, the copyright holder has to grant rights to someone to use his or her work.
While stock photography sites sometimes do have photos people are allowed to use for free, or size/resolutions they do not restrict, it is advisable that you understand exactly how the site allows use.
In the article Understanding Royalty Free and Rights Managed Stock Photography, you can learn about the basic rules for licensing stock photographs.
It is sold by the image, as royalty free images. Royalty free stock photography does not mean that the photo is copyright free - and definitively may not be free to use. It means that you can buy the use of an image, and use it a certain number of times, on a single project. Other people can purchase the right to use the same image for their own uses. The photos are much cheaper than stock photos were in the past, and much cheaper than royalty managed photos, which have some exclusive features and can be very expensive.
If you are considering using stock photographs on your website or in a desktop publishing project, read Using Stock Photography for your DTP Project, and understand the license you are acquiring to the images you want to use. There are now different models for getting stock photographs, and depending on your needs, you may want a subscription, or to buy the right to an image individually, depending on how many different images you expect to need regularly.
If you are on a limited budget, try using the information in this article on copyright free & stock photography to locate images which you will not have to pay for, and feel secure you are not infringing a copyright.