DOQQ

This is a digital orthoquarter quad, which is a georectified raster image developed from aerial photos, in this case in black and white although it could have been in false color. I liked that it is from a site for the CA Dept. of Conservation, and the arrow points to their headquarters. The undated article states, in part "Last July, DOC purchased 21 digital linear tapes in a format called UNIX TAR from the U.S. Geological Survey for $28,000 " the cost of reproduction. The tapes contained 10,289 DOQQs, comprising a highly detailed computerized map covering most of the state.
http://www.conservation.ca.gov/index/PublishingImages/You_are_here.jpg