COPYRIGHT AND USAGEThe materials (images, video, documents, etc.) available on this website may be protected by copyrights owned by private individuals or organizations, and may be subject to restrictions on use. Copyrighted materials, in most circumstances, cannot be used or distributed without the permission of the copyright holder. (NIST does not maintain current contact information for copyright holders.)
The National Institute of Standards and Technology (NIST) is an agency of the U.S. Commerce Department.