1832: A clipping of the French omnibus. Omnibus dates from 1829 and was used to describe a "long-bodied, horse-drawn, four-wheeled public vehicle with seats for passengers", from the French voiture omnibus (carriage for all, common (conveyance)), from the Latin omnibus (for all), dative plural of omnis (all), ablative of omnia, from the primitive Indo-European hep-ni- (working), from hep- (to work; to possess) or hop- (to work; to take). Bus was thus a convenient shortening to describe the (then horse drawn) forms of public transport and subsequent uses by analogy with transporting (even weightless) stuff is derived from this. The present participle is omnibusing or omnibussing and the past participle omnibused or omnibussed; the noun plural is either omnibuses or (for the public transportation) omnibusses; the attractive omnibi unfortunately wholly non-standard. The sense "to travel by omnibus" dates from 1838; the transitive meaning "transport students to integrate schools" is American English from 1961. The meaning "clear tables in a restaurant" is first attested 1913, probably from the four-wheeled cart used to carry dishes. The electrical sense is derived from a figurative application of the automotive sense; the use in computer architecture followed this model. “To miss the bus” in the figurative sense of a lost opportunity is from 1901 and credited as an Australian invention (although the OED lists a figurative “miss the omnibus” from 1886). It was most famously used by Neville Chamberlain (1869–1940; UK prime-minister 1937-1940) during the "Phoney War". On 5 April 1940, confident the previous eight months spent building up armaments meant the west was now invulnerable to invasion, Chamberlain felt sufficiently confident to declare to the House of Commons "Hitler has missed the bus". The Wehrmacht invaded four days later.
The bus wars
For IBM, the decision in 1980 to adopt an open bus architecture for the original PC was a good idea at the time. Anticipating the PC being a niche-market product, the open bus was seen as a way to encourage sales by encouraging smaller manufacturers to produce expansion boards (cards) but not involving IBM in what would be an activity of marginal profitability. However, the PC soon became a huge sales success and the open bus meant manufacturers were soon producing their own PCs, not just the expansion cards and by the mid-1980s, IBM weren’t best pleased to find of all the PCs being sold, relatively few were genuine IBMs. Their response in 1987 was to develop a proprietary bus for the new range (the PS/2 PCs & the OS/2 operating system) which, unlike open architecture, would attract royalties from the cloners, the new bus called Micro Channel Architecture (MCA). Technically MCA offered many advantages, most obviously an early implementation of the soon-familiar plug’n’play which (usually) worked surprisingly well as well as a twenty percent increase in bus speed. Apart from the cost, the main drawback was the lack of backward compatibility; not only did third-party manufacturers have to re-tool to design and produce new motherboards & cards, consumers could not re-use their existing cards, something important at the time.
A pack of the biggest cloners didn’t like this and responded with their own design, an enhancement of the original AT (which they re-named Industry Standard Architecture (ISA)) called Extended Industry Standard Architecture (EISA) which either matched on felt only slightly short of the technical improvements provided by MCA. EISA advantages were (1) cost breakdown, (2) it was free for anyone to use and (3) backward compatibility. IBM wasn’t impressed, stressing the technical superiority of 16 & 32-bit MCA, noting a mixing of 8, 16 and 32-bit cards in the one bus would inevitability result in one device getting very hot, leading to what they called “…a silicon barbeque”. For a while, the bus wars raged and while it’s true MCA was better, it wasn’t that much better so for many the additional costs were hard to justify. Had the bus wars continued, it could have gone either way because while EISA was free, it was a cul-de-sac, it’s development potential limited whereas IBM could have both improved MCA and lowered its licensing fees. However, the development of the the PCI (Peripheral Component Interconnect) bus rendered both MCA and EISA (and the short-lived VESA) obsolete. When USB (Universal Serial Bus) devices became ubiquitous, the whole system board became unknown to all but the nerds.
Bus scene in Mean Girls (2004).
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