Hot answers tagged

72

Keyboards have an asterisk because typewriters did, long before computers existed. Typewriters, particularly mechanical ones, typically made a number of compromises to reduce the number of keys required. For example, many didn‘t have 0 or 1, and people used O and I or l instead. Likewise, × wasn’t needed since x could be used instead, or · (. half-up). The ...


72

And if you go back further, e.g. to the ENIAC, you'll see a word size of 40 bits. And if you go back even further, to mechanical calculators, you'll see word sizes determined by the number of decimal digits they can represent. And that explains the approach: Computers originally were meant to automate calculations. So you want to represent numbers. With ...


63

Computer terminal keyboards needed to reproduce the symbols available on punched cards and paper tape. In the US, punched cards dominated the data-processing industry (communications uses tended to paper tape). IBM punched card codes in particular were significant in the industry. The IBM 026 keypunch (and its replacement the 029) had an asterisk. By the ...


50

Yes, Windows 95 really was released on August 24, 1995; I still have the special issue of The Times that heralded the event. But I distinctly remember thinking that it was late, back at that time. That’s not surprising: Microsoft had been trumpeting the release of the next version of Windows for a long time, and there was widespread coverage in the media ...


46

FORTRAN was, at the time(*1), lacking almost everything, from string handling to all I/O beside reading numbers from cards or tape. Heck, not even integer size was guaranteed across machines. No real way of structuring or flow control beside GOTO — even subroutines/functions were only integrated a year before with FORTRAN II. For most parts, FORTRAN is a ...


41

Fast multiplier circuits as used today take enormous amounts of logic, far beyond what would have been cost-effective (or perhaps even possible) in the mid-70s for an inexpensive microprocessor. Even slow multiplier circuits (as appear later on chips like the 6809, 68000 or 8086) use a fair bit of logic and would have very considerably added to the cost, ...


38

You don't need it Multiplying two arbitrary bytes together has limited practical value. (If you want to multiply by a constant you can hardcode the optimal sequence of instructions to do so.) Obviously it would be nice to have but the expense isn't worth it. In an arcade game... you basically never need to multiply a thing. To draw lines or circles, you can ...


34

TL;DR; Punch card code is not binary but a collection of n out of m encodings. Long Story Yes, really a long story, so I'll only cover the main line from Hollerith to EBCDIC. there are many sidelines for special equipment, situations and as used by different manufacturers. Some covering up to 7 holes but all mostly compatible in the basic Numeric/Alpha ...


32

The meeting that defined the requirements of the new language took place on May 28–29, 1959. Charles Phillips prepared a memo several months later summarizing the decisions made at that meeting. Its listing of requirements is reprinted on page 201 of the ACM’s History of Programming Languages. a. Majority of group supported maximum use of simple English ...


23

Uppercase text only needs six bits per character. The fundamental mistake that you are making is assuming that punch codes were binary numbers. They were not. The encodings were patterns, combinations of of zero, one, two, or three holes. This is a reference card in IBM 5081 format: The row numbering was somewhat odd, for historical reasons: 12, 11, 0, 1, ...


22

When you have a small transistor budget, it is considerably easier to design your circuitry around a single representation format - the most capable one - and treat converting other formats to and from it as a separate problem. That's how the 8087 and 68881 were both designed. Today, there are enough transistors sloshing around in the average CPU that ...


21

FORTRAN was originally developed for the IBM 704 computer, which stored integers in sign-and-magnitude format. In the original documentation, it supports fixed-point variables, which used the machine’s native format, floating-point variables, and unsigned fixed-point constants, which were intended for line numbers and subscripts. These would be translated ...


20

Longer words mean more bits can be processed at once. An 8 bit processor can perform a 32 bit calculation, but it has to do it in 4 stages of 8 bits each. A 32 bit processor can do it in one stage. Since early computers had limited clock speeds due to slow electronics increasing the word size was one of the few options available to improve performance. In ...


20

Although you have many correct answers describing the nature of the coding used in punched cards, no one has touched on the mechanical properties of the cards. Regular users of punched cards in the past would be familiar with this issue, as getting cards through the mechanics of a fast card reader regularly and repeatedly was a major issue at the time. If a ...


18

For a long time (starting late 1992/ early 1993), what was to become Windows 95 went under the name of "Chicago". Only in september 1994 (beta 1.4 / build 189), did it become Windows 95. Microsoft must have been reasonably sure they were going to release in 1995 by then. Early Chicago Usability Testing builds - 1992/93 Last Chicago labeled build - ...


17

My second guess is CTSS. It was operational in 1961, but at that time had only tapes for user file storage. I suppose that tape name records don't constitute 'metadata' in the sense required by this question. A disk was added somewhere around 1962 to 1963. The CTSS Programmer's Guide from 1963 mentions the installation of the IBM 1301 disk file; and 5) ...


16

Short Answer: At the time PCI was devised, the x86 bus had already gone a long way toward being less chip specific. PCI is maybe a clean design, but some choices for signals are still 'intelish' Moving bus definition from following what a certain CPU implementation needs toward a more generic structure opens up more ways for future CPU development than ...


13

A possible answer occurs to me: it might be precisely because of the slow memory. Say you want to add a pair of ten-digit decimal numbers, SUM += VAL, on a 6502. That chip has a BCD mode in which it can add two digits at a time; it has to do everything through an 8-bit accumulator. So we need a loop of five iterations, which we might unroll for speed. Each ...


13

Round holes might have been 'stiffer', but rectangular holes won on packing density. When IBM invented the 80-column card (up from the previous 40-column Hollerith card of the same size), they determined you could get more columns per card by using rectangular holes. IBM's own history describes two competing designs: the 80-column rectangular-hole card we ...


12

The reason to use * instead of × is disambiguation. × looks very similar to x now, even more so in the early days of computing, before the laser printer became ubiquitous and you needed typesetting software and a printing press to produce an × that was distinguishable from an x. According to this post, we can blame Fortran: While it is now common practice ...


12

TL;DR: That being so, the assigned goto is just an indirect jump through the variable. Right. But in actual fact, the assigned goto had to be given a list of statement numbers No, it had not. The list was always an optional one. If not given, the GOTO was simply executed without any further check. What purpose does the statement-label list serve? It's ...


12

The early-to-mid 1990s was a time where the future of the Personal Computer was very much up for grabs. Both the "Wintel" monopoly as a whole, and each part individually, where not at all set to be the foundations of the future PCs. Even if we were to assume that x86 would "win", we had OS/2 and to a lesser extent BeOS as competitors on ...


11

(This answer has now been determined not to satisfy the now-clarified requirements of the question. Nevertheless, the discussion seems useful, if only in my own mind, so I will leave it here. But see my other answer about CTSS.) I will guess that the standard answer for 'first' applies here: the Atlas Supervisor. Section 6 of the linked document talks ...


10

Here's a BBC News article describing the midnight retail availability of Windows 95 on 24th August 1995. This Mashable article claims to show a photograph of a buyer at the Australian launch on the same date. It gives a November date for Japan.


9

Because it was already reserved for batch file command-line parameters. Early DOS versions (1.x) did not support environment variables at all. They did, however, support batch files and parameter substitution using the %n syntax (source). The character % was already reserved for that purpose, and already had to be escaped as %% in batch files; it made sense ...


9

Your second and third points are disadvantages from the user’s perspective. Looking at things from the manufacturers’ perspective, SLI has one significant advantage: it raises the maximum number of graphics cards in a single system, which automatically raises the market’s ability to envision buying more graphics cards. SLI started with 3dfx, where it was ...


9

I'd have added this in a comment but don't have enough rep. If you read far enough into the IBM history link given by another-dave in his answer, you'll find this quote that indicates the rectangular holes were in fact stronger: As well as handling more data, the unique rectangular hole was stronger [emphasis mine] and more compatible with the wire brushes ...


8

Circa 1950 Royal typerwriter. Top row of keys, second from the right. What do you see?


8

Except for the full set of upper- and lowercase letters, there was. The Soviet character encoding standard GOST 10859-64 included all of the ALGOL-60 special characters, and there were card punchers controlled by electric typewriters (Consul-260) with a standard-compliant character set. Note the lack of distinct Latin letters graphically equivalent to ...


8

However, there were other possibilities, such as a later IBM format that used round holes. Not only later, but also previous IBM formats used round holes. Similar next to all other contemporary (1930s) manufacturers (Powell, CDC, Honeywell, etc). Intuitively it seems to me that round holes would be better from a mechanical stiffness viewpoint, making the ...


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