PhotoDisc, Inc. based in Seattle, was a publisher of digital stock photography free of royalties. It was founded in 1991 by Tom Hughes, Mark Callaghan and Mark Torrance, who later became the chief executive officer and chairman. After receiving the catalog in the mail, customers would write or phone the office and order the photos or pre-made collections by charter artists Clement Mok or Nick Koudis which would then be shipped to them on CD-ROM.