Recent News

click here for news about my visit to MIT in fall!
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Wow, autumn is here already. 1999 is a Mersenne prime exponent year of my life, and I've been working full time on MMIX. Hurray, I just finished A programmer's introduction to MMIX (424KB of compressed PostScript) (a supplement to The Art of Computer Programming, Volume 1), and I'm looking forward to paying rewards to anybody who spots an error in this hot-off-the-press tutorial!

News flash, November 17:
Hurray hurray, I've also just finished a book called MMIXware, which will be number 1750 in the Springer Lecture Notes in Computer Science. This one weighs in at 550 pages, and I'm told that I will have printed copies to show in Boston when I speak to the local ACM chapter on December 15! (See below.)

Earlier this year I celebrated the appearance of a new 700-page book Digital Typography that I hope people will like. And December brought yet another new book, MMIXware---this one only 550 pages long. Check it out!

Usually I must stay home and work so that I'll be able to move on to other projects --- like Volume 4 --- very soon. But here is a calendar of a few Public Appearances that have either already happened or are planned for later this year:

Tuesday, February 9
Computer Musing lecture at Stanford: MMIX, a RISC computer for the new millenium
Friday, February 19
Digital Typography, a lecture cosponsored by CSLI and by the Associates of the Stanford University Libraries
Wednesday, March 3
Computer Musing lecture at Stanford: a buzzword-compliant pipeline simulator for MMIX
Wednesday, May 5, 10am
speaking at MSRI in Berkeley about The Birth of the Giant Component
Saturday, August 28, beginning at 10am
West Coast MMIX Day
Sunday, September 12, after dinner
speaking to the UK TeX Users Group at their meeting in Oxford
Tuesday, September 14, noon
speaking at Oxford Symposium in honor of C.A.R. Hoare
Friday, September 17, afternoon
speaking at The Computing Laboratory at the University of Kent in Canterbury, as part of a symposium to honor Heather and Peter Brown
Tuesday, October 26, 10am (and continuing thru the afternoon)
demonstrating MMIX software at Harvard
Friday, October 29, 4:15pm
speaking at the MIT Combinatorics Seminar about ``Linear Probing and Graphs''
Tuesday, November 9, 4pm
speaking at the MIT Theory of Computation seminar about Dancing Links
Friday, December 10, 4:15pm
speaking at the MIT Combinatorics Seminar about ``Lattices of Trees''
Wednesday, December 15, 6:30pm
speaking to the Greater Boston Chapter of the ACM about MMIX
Friday, December 24, 11pm
Playing the continuo organ at First Lutheran Church of Palo Alto, in a performance of Charpentier's Messe de Minuit pour Noël

Also, I'll be visiting MIT during the fall and giving a half dozen or so lectures: see below. During the months of September, October, November, and December, I will not be reading any mail about purported errors in my books, because all the master files are at Stanford in a standalone computer that will be turned off. After Y2K I'll get back to the routine of bug-fixing as usual. (Any rewards for bugs reported during my downtime will be increased by adding interest compounded from the time they were received.)

A Hearty Welcome to Grandson #2!

Carter John Knuth
born 19 April 1999
8 lbs, 10 oz
22 inches
Julie and John doing fine (modulo sleep)
pictures taken at age = 8 hours

What is a kilobyte?

Many people (and many online dictionaries) claim that a kilobyte (kB or KB) is 2^10 bytes, and that a megabyte (MB) is 2^10 kilobytes, etc.

I'm a big fan of binary numbers, but I have to admit that this convention flouts the widely accepted international standards for scientific prefixes.

Therefore I propose a simple way to resolve the dilemma and the ambiguity: Let us agree to say that

2^10 bytes is a large kilobyte, abbreviated KKB;
2^20 bytes is a large megabyte, abbreviated MMB;

and so on up the line: Large giga-, tera-, peta-, exa-, zetta-, and yottabytes are GGB, TTB, PPB, EEB, ZZB, and YYB, taking us up to 2^80. (Notice that doubling the letter connotes both binary-ness and large-ness.)

These proposals were motivated by the suggestions in 1995 of IUPAC-IDCNS (the International Union of Pure and Applied Chemistry's Interdivisional Committee on Nomenclature and Symbols), which were extended by IEC TC 25 (Technical Committee 25 of the International Electrotechnical Commission), chaired by Anders J. Thor. According to those committees, 2^20 bytes should be called a "mebibyte" and abbreviated MiB; 2^40 bytes should be called a "tebibyte" and abbreviated TiB; etc. The members of those committees deserve credit for raising an important issue, but when I heard their proposal it seemed dead on arrival --- who would voluntarily want to use MiB for a maybe-byte?! So I came up with the suggestion above, and mentioned it on page 94 of my Introduction to MMIX. Now to my astonishment, I learn that the committee proposals have actually become an international standard. Still, I am extremely reluctant to adopt such funny-sounding terms; Jeffrey Harrow says "we're going to have to learn to love (and pronounce)" the new coinages, but he seems to assume that standards are automatically adopted just because they are there. Surely a huge number of standards for other computer things, like networking protocols, have been replaced by better ideas when they came along. Thus I hope it still isn't too late to propose what I believe is a significantly better alternative, and I still think it unlikely that people will automatically warm to "mebibytes". Indeed, the last time I looked (June 28), names like "" were being offered for sale but with no takers! I might, however, want to buy into a name like And even in the unlikely event that mebibytes do catch on, MMB surely wins over MiB as their abbreviation. [See also the discussion by Kevin Walsh.]

Lectures at MIT

I will be giving a series of lectures on Wednesday afternoons at MIT this fall --- more precisely, on October 6 through December 8, except for October 20 and November 10 and November 24 --- on the general theme ``Things a Computer Scientist Rarely Talks About.'' This is part of the God and Computers project organized by Anne Foerst. You can watch these lectures on Dr. Dobb's TechNetCast!

Click here for the ``recent news'' that was current at the end of 1998, if you're interested in old news as well as new news.

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