MMM deserves all the attention it gets, but there's more!
1. I've got to track down the source of the quote (it may be the linked video), but Brooks has said that the most important architectural decision he made was to have an eight bit byte rather than the cheaper 7 bits (Edit: 6 bits) being considered for the IBM 360. To call that influential is an understatement.
2. And he has said the most important management decision was sending Ted Codd to graduate school, where Codd laid the foundation for what became relational databases.
3. A paper [0] he co-authored with Amdahl and Blaauw introduced the term 'architecture' to computer hardware, later borrowed for software. From the first page: "The term architecture is used here to describe the attributes of a system as seen by the programmer, i.e., the conceptual structure and functional behavior, as distinct from the organization of the data flow and controls, the logical design, and the physical implementation."
He gave an interesting talk at the 50th anniversary of the International Conference on Software Engineering (ICSE) a few years ago, [1]
[0] 'Architecture of the IBM System/360', Amdahl, Blaauw, Brooks.
> eight bit byte rather than the cheaper 7 bits being considered for the IBM 360
That's 8-bit vs. 6-bit bytes. See "Interview: An interview with Fred Brooks", Communications of the ACM, Volume 58, Number 11 (2015), Pages 36-40 https://dl.acm.org/doi/fullHtml/10.1145/2822519 .
> Gene's machine was based on the existing 6-bit byte and multiples of that: 24-bit instructions and a 48-bit instruction or floating point ... Of all my technical accomplishments, making the 8-bit byte decision is far and away the most important. The reason was that it opened up the lowercase alphabet. I saw language processing as being another new market area that we were not in, and could not get into very well as long we were doing 6-bit character sets.
From your [0], "Architecture of the IBM System/360" (1964) at https://cpb-us-w2.wpmucdn.com/sites.gatech.edu/dist/8/175/fi... see the section "Character size, 6 vs 4/8", which discusses 4/6, 6, and 8-bit codes and the reasoning for 8-bit, and which comments:
> The selection of the 8-bit character size in 1961 proved wise by 1963, when the American Standards Association adopted a 7-bit standard character code for information interchange (ASCII).
FWIW, [0] is from April 1964. He also used "computer architecture" in the earlier "Architectural Philosophy", which is chapter 2 of the 1962 book "Planning A Computer System" concerning Project Stretch, at https://archive.org/details/bitsavers_ibm7030Plam_46781927/p...
I'd guess because it's not an even number. I don't know why even number of bits were considered infeasible, but there hasn't been a single computer architecture with odd number of bits as word length: https://en.wikipedia.org/wiki/Word_(computer_architecture)
??? The table on that article contains plenty of architectures with odd bits per word, for example the Apollo Guidance Computer (15). Odd bits often resulted from sign or parity bits. And I'm shocked to see decimal digits were sometimes encoded as 5 to 7 bits to a digit (bi-quinary coded decimal) rather than 4 (binary coded decimal), e.g. in the IBM 650 (10 digits and a sign bit), which used 71 bits per word - a prime number! Of course "bit" is not the right term here, as software can't access them. But there are 71 physical switches exposed to the user for input.
1. I've got to track down the source of the quote (it may be the linked video), but Brooks has said that the most important architectural decision he made was to have an eight bit byte rather than the cheaper 7 bits (Edit: 6 bits) being considered for the IBM 360. To call that influential is an understatement.
2. And he has said the most important management decision was sending Ted Codd to graduate school, where Codd laid the foundation for what became relational databases.
3. A paper [0] he co-authored with Amdahl and Blaauw introduced the term 'architecture' to computer hardware, later borrowed for software. From the first page: "The term architecture is used here to describe the attributes of a system as seen by the programmer, i.e., the conceptual structure and functional behavior, as distinct from the organization of the data flow and controls, the logical design, and the physical implementation."
He gave an interesting talk at the 50th anniversary of the International Conference on Software Engineering (ICSE) a few years ago, [1]
[0] 'Architecture of the IBM System/360', Amdahl, Blaauw, Brooks.
[1] https://www.youtube.com/watch?v=StN49re9Nq8