However, many free libraries that have popped up recently, some with images just as good as the expensive sites.
Here are my favorite image libraries in no particular order.
Unsplash adds 10 new royalty-free photos every 10 days, often of breathtakingly beautiful landscapes. Just scroll down the home page to see foggy rivers, faraway mountain ranges or even battered signs in all their high-resolution glory. This is currently my favorite site for large “hero” images that I put on my website homepages.
FreeImages has one of the most exhaustive directories of open-source images around and has excellent search capabilities to find just the image you are looking for. While most stock-photo sites focus on a small niche (such as landscapes or business photos), FreeImages offers thousands of pictures from a wide range of categories. This is the go-to resource for many web designers.
Pixabay is a web designer's dream. The images here are very easy to find, are absolutely brilliant, and most don't require any attribution at all.
Gratisography's collection is, in a word, incredible. Built by the talented artist and web designer Ryan McGuire, this site features some of the most evocative images on the web and they requires no attribution whatsoever.
Pexels offers thousands of high-resolution images for free and without any need for attribution. It focuses on business and technology collections and is a high-quality, free alternative to expensive stock photo sites like Getty Images and Shutterstock. No more spending hours looking for the perfect image of someone typing on a laptop. And no more paying hundreds of dollars to use a photo, either.
Picography is the simplest site on this list. It is a scroll-through gallery of random shots offered by a handful of professional photographers. You can't search it but this site is perfect for looking for interesting photos.
MorgueFile is perhaps the easiest site to use on this list. It uses a very streamlined layout and carefully curated list of photos. Its selection isn't as large as that of some of the other sites on this list, but the photos included cover a wide range of topics.
New Old Stock is a collection of antique photos, many taken by government agencies or discovered in estate sales and can be very entertaining to check out.
Public Domain Archive, an expansive online collection of images, many with striking symmetry and muted colors.
Attribution and licenses explained.
I feel compelled to close this post with some words about copyright. When you do a Google search for images, the resulting photos are not necessarily free to immediately use. In most cases, the photos are still covered by photographers' copyrights.
To keep you out of copyright trouble, I’ve only listed websites here where the license is generally pretty easy to find. Here are two license types you're likely to find on these sites:
Creative Commons zero means that you can use the photos in any way you'd like, without asking permission.
Creative Commons with attribution means that you can use the photo in any way you want, as long as you credit the creator of the photo.
Attribution is simple: If you include a photo on one of a web page, add text that cites the photographer and be sure to include a link to his or her site, if there's one. Also, be sure to check each website's license page for specific details.