Hello SIGCIS, I had some good off-list replies, so here's a wrap up for the benefit of the community. We've decided to use "Spacewar" in the text, with a note or parenthetical aside that Steve Russell prefers the name with an exclamation point. Eagle eyed readers may note that this is a slight variation from my original suggestion of noting that Spacewar! is the "official name." That's because a couple of responses have made me wonder what "official" would even mean. We already knew the game became famous in the 1970s and 1980s as "Spacewar". We also have a generally accepted idea that Steve Russell is on the record as liking the title more with the exclamation point. Peggy Kidwell of the National Museum of American History pointed me towards this catalog entry for a 1962 paper tape. https://americanhistory.si.edu/collections/search/object/nmah_1064201 That's just one year after the game was written. According to the catalog, "in compartment B - Friden Business Systems - Tape-Talk, X Good Space War. Also marked in punches: SPACEWAR 3.1 24 SEP 62 PT. 1" So it was written for humans as "Space War" and coded on the tape itself as "SPACEWAR". The tape was a gift from DEC itself, which makes sense as DEC is said to have been instrumental in spreading the game to show off and diagnose its display screens. Arthur Daemmrich at the Lemelson Center was also kind enough to look into this. He supplied me with a DEC brochure that used the game to sell the PDP-1. The cover gives the name as "SPACE/WAR" (on two lines) and the interior calls it both "SPACEWAR" and "Spacewar." I was able to find a copy of the brochure here: https://www.masswerk.at/spacewar/pdp-1-computer-and-spacewar.html. Arthur also raised the question with one of the original MIT programmers of the game, who did not recall the exclamation point being an integral part of the name. (I'm reluctant to share the full message without permission). I found a detailed technical examination of the game by Norbert Landsteiner at https://www.masswerk.at/spacewar/inside/. The author calls it Spacewar! throughout, but there is a suggestion that the filenames holding the binary contents of the original paper tapes, such as "spacewar2B_2apr.bin" are transcriptions of the labels on the original tapes. These do not contain the point. (Full list at https://www.masswerk.at/spacewar/sources/) The site also mentions code to punch "SPACEWAR" into tape headers. Since paper tapes didn't have a filename, the filename of the digital image would have presumingly been derived from a handwritten label, right at the start of the tape. Apparently, someone had written "Spacewar SA 5" on the tape. (Or, since there was a little program to punch a pattern reading "SPACEWAR" onto a tape, it might have been the title-punch and a handwritten "SA 5".) Finally, Arthur also sent an early article on the game, from Creative Computing in 1981. This _does_ include the exclamation point in the game's title and is thus the earliest recorded usage of it we've so far stumbled on. Chronologically this is between Brand's 1972 article and Levy's 1984 book. See https://archive.org/details/creativecomputing-1981-08/page/n59/mode/2up. The author, J.M. Graetz, was another of the MIT group behind the game. There's an earlier report by Graetz in the 1962 DECUS proceedings: http://bitsavers.org/pdf/dec/decus/confProceedings/DECUS_1962.pdf in which the name does have the point but is also capitalized: "SPACEWAR!" So putting it all together: "Spacewar!" is the preferred name for at least some of the members of the original hacker collective that produced the game at MIT and (as "SPACEWAR!") has been on record as such since 1962. On the other hand, it is not clear that the point was ever part of the name as written on the MIT program tapes holding the game or used when the name was punched as a header onto the tape. We _do_ have clear evidence that the PDP-1 game as distributed and advertised by DEC was called "Spacewar" with no point. So that would seem to be the "official" name to describe its use and influence beyond MIT. As using the name sometimes with and sometimes without the point depending on context would be confusing we'll standardize on the pointless DEC/Levy/Brand version of the name for the purposes of our book. Some of you may also feel that "pointless" is a good summary of this thread. Best wishes, Tom