When strung out in this manner, the pace of change seems breathtaking: from writing to the codex, 4,300 years; from the codex to movable type, 1,150 years; from movable type to the Internet, 524 years; from the Internet to search engines, nineteen years; from search engines to Google’s algorithmic relevance ranking, seven years; and who knows what is just around the corner or coming out the pipeline?