In Christina Engelbart‘s “Tips for blogging about Doug Engelbart and his work” post, she mentioned granular addressability and the “Purple Numbers” which were inspired by the NLS/Augment implementation. For anyone simply commenting upon aspects of the “Augmenting Human Intellect” paper, her instructions in the “Tips for Blogging…” post are excellent and sufficient.
But for programmer-types, and anyone interested in more discussion of these concepts, there’s lots more information available to read and study. I first learned about purple numbers from reading entries in Eugene Eric Kim‘s blog, and tonight am finding links to much more discussion by him and others. A search on his blog for “purple” turns up a bunch of entries about it. One of the earlier ones, “A Brief History of Purple Numbers” from August 2003, corrects and expands upon “Why is it Purple?” by Chris Dent in late July 2003. Those two pages summarize most of the history. There’s also a bit on “The History of Purple Numbers” written by Christina Engelbart in February 2005.
In 2004 Eugene Eric Kim posted “Tim Bray on Purple Numbers“, in response to Tim’s post “Purple Number Signs” in which Tim implemented, then removed, then put back the purple numbers in his post. Tim Bray discusses several concerns, then points to postings by Simon Willison, Mark Nottingham, and the Chris Dent history post above. In the same timeframe Chris Dent posted “Big Day for Purple Numbers” in response to Tim Bray and Jonas M Luster. (Jonas Luster’s old site seems to have moved; I haven’t tried to use archive.org to find the original posts Chris referenced.)
Chris Dent has a series of entries from 2005, “Fundamentally Purple“, “Purple Response“, and “Purple Identification” which discuss some concerns and goals of these persistent identifiers. A Google search for “purple site:burningchrome.com” yields a bunch more of Chris Dent’s posts about this topic. Eugene Eric Kim refers to more of his discussion with Chris Dent in “Purple Numbers: Optimized for Synthesis” from May 2005.
Eugene Eric Kim has purple-0.4 on his wiki, but his blog post indicates it was up to at least version 0.9 as of February 2006. The wiki page for v0.4 points to “An Introduction to Purple” from August 2001, which I think is the earliest write-up I’ve found.
The Boris Mann comment reminds me that some other time we’ll have to follow some thought vectors starting with other posts on SGML and HTML and XML and other markup languages by Tim Bray, as well as some regarding typesetting and typography and computer-based tools like TeX and Metafont developed by Donald Knuth, extensions such as LaTeX from Leslie Lamport, and other such things…