From the About us page:
Morguefile is a free photo archive “for creatives, by creatives.” Founded by Michael Connors in the early Internet days of 1996, the site was created to serve as a free image exchange for creative professionals and teachers to use in their work. This same mission remains true today: we are a community-based free photo site, and all photos found in the Morguefile archive are free for you to download and re-use in your work, be it commercial or not.