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102 votes
Accepted

Why were programs entered on punch cards instead of paper tapes?

The basic issue that paper tape is hard to edit. In theory you can cut the existing tape and splice in a new section, but in practice there is no easy way to find the correct location except by ...
alephzero's user avatar
  • 6,656
65 votes

Why are punch card readers no longer in use?

The main reason punched cards aren't used any longer is density. A one-inch stack of cards is only 142 80-byte records (assuming the usual practice of encoding one byte per column). So if you need ...
Ken Gober's user avatar
  • 11.4k
64 votes
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Is the substitution "ss" for "ß" on mainframes due to the SS being the largest customer of IBM punched cards outside the USA?

The ß -> ss transcription goes back centuries (see e.g. the German Wikipedia entry on the ß), so: no.
Michael Graf's user avatar
  • 10.1k
53 votes
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What did code on punch cards do with the other six bits per column?

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 ...
Raffzahn's user avatar
  • 224k
45 votes

Do the holes in Jacquard loom punched cards represent input data or program code?

Do the holes in Jacquard loom punched cards represent input data or program code? yes. Let me tell you a story. Somebody I used to work with many years ago was flying into the USA (or it might have ...
JeremyP's user avatar
  • 11.7k
42 votes

Why were programs entered on punch cards instead of paper tapes?

Punch cards long long long predated paper tape. But there's a practical consideration you're not thinking of. If you had ever used punch cards and paper tape, you'd know: Punch cards can be dropped, ...
davidbak's user avatar
  • 6,289
41 votes

Is the substitution "ss" for "ß" on mainframes due to the SS being the largest customer of IBM punched cards outside the USA?

TL;DR: NO When I was a child, my German teacher (in a non-German speaking country) told us that the typed form for the letter "ß" in use in mainframes at that time was "ss" ...
Raffzahn's user avatar
  • 224k
36 votes

Why are punch card readers no longer in use?

Nice Question :)) Short answer: Density - It just takes way too much cards to store anything useful. (And no, there is no way back in the good old time of optimized data structures) When you ...
Raffzahn's user avatar
  • 224k
32 votes

What did code on punch cards do with the other six bits per column?

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, ...
JdeBP's user avatar
  • 2,288
32 votes
Accepted

What does this 1970s punched-card format mean?

The symbols are as follows: (…) are used for grouping. X → Value doesn't matter I → Numeric (integer) A → Alphabetic (in this case one of N, S, E, or W) , → Used to separate each column or group ...
Alex Hajnal's user avatar
  • 9,350
31 votes

What did code on punch cards do with the other six bits per column?

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 ...
Brian Tompsett - 汤莱恩's user avatar
26 votes
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Was any indentation-sensitive language ever used with a teletype or punch cards?

I agree to an extent that COBOL was "indentation-sensitive", but it really wasn't "indentation-sensitive" but rather "column-sensitive". The original COBOL coding format ...
mannaggia's user avatar
  • 3,264
23 votes

Was bootloading from punch cards possible on System/370 machines?

Sorry for the narrative here, but it answers the OP's question directly by personal experience. The text is too long for a comment. "Was bootloading from punch cards possible on System/370 ...
timetraveller's user avatar
22 votes
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Was bootloading from punch cards possible on System/370 machines?

TL;DR: Yes, a /360 (*1) can boot from any device connected to a channel. A /360 can boot from any device able to answer to a basic read command. Whatever is delivered will be executed. There is no '...
Raffzahn's user avatar
  • 224k
21 votes

How late were 80-column punched cards relevant?

The question is a bit contradictory as it seems to ask for multiple, possibly mixed-up, items: Use of physical cards Use of card originated conventions Use of the word card as professional term In ...
Raffzahn's user avatar
  • 224k
20 votes

Was any indentation-sensitive language ever used with a teletype or punch cards?

COBOL and FORTRAN are both (or were) highly indentation-sensitive, precisely because they were created at a time when punch-cards were the most common data-entry medium. Modern editors and compilers ...
Eight-Bit Guru's user avatar
18 votes
Accepted

Was there a way to directly print out a deck of punch cards without involving a computer?

Punch cards predate computers, so yes, of course, there was. A printing tabulator like the IBM 402 or the IBM 407 should be able to do that.
Michael Graf's user avatar
  • 10.1k
17 votes

Do the holes in Jacquard loom punched cards represent input data or program code?

Program code for modern CPUs, in practice, consists of opcodes which tell the CPU what operation to perform, and operands which provide data to operate on. In RISC CPUs these are necessarily both ...
Chromatix's user avatar
  • 16.8k
17 votes

How much data could be stored on a single punched card?

it says the original 8inch floppy disk from 1971 could store 80kb of data equivalent to that of 3000 punched cards Given, the text is a bit misleading, as it mixes up firsts. While it is true that ...
Raffzahn's user avatar
  • 224k
17 votes

Why were programs entered on punch cards instead of paper tapes?

Punch cards and paper tape are suited for different tasks. Punch cards work better when the size of the data is not known in advance. How long would you manufacture the unpunched paper rolls? If ...
DrSheldon's user avatar
  • 16k
16 votes

How were 18-bit instructions encoded in paper tape?

The answer is invariably specific for a particular computer, and indeed may be specific depending on what is doing the reading (say, hardware bootstrap versus software loader, or what it's reading ...
dave's user avatar
  • 35.7k
15 votes

Do the holes in Jacquard loom punched cards represent input data or program code?

All code is data. But not all data is code. For example, you can take a digital photo and the numbers represent light intensity across a 2D rectangle. Nobody would dispute that this is data but not ...
Artelius's user avatar
  • 1,030
15 votes

Who introduced the standard 8-bit punched tape, and when?

TL;DR: 5 hole (*1) tapes were developed as part of Murray's teletype system, the first (successful) to use typewriter keyboards as well as punch tapes. Wider (more holes) paper tapes are compatible ...
Raffzahn's user avatar
  • 224k
14 votes

Were round punchcard holes mechanically stiffer?

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 ...
dave's user avatar
  • 35.7k
14 votes

How much data could be stored on a single punched card?

Each hole in a card represents one bit: It either can be punched, or not punched. The holes in a classic card are arranged in 80 columns and 12 rows. 80 x 12 = 960, so the most amount of information ...
Solomon Slow's user avatar
  • 2,101
14 votes

How late were 80-column punched cards relevant?

IBM 80-column cards were used in the NASA Johnson Space Center Shuttle Mission Simulators (SMS) (designed in the late 1970s) until the late 1990s. The simulators contained actual shuttle flight ...
Organic Marble's user avatar
14 votes
Accepted

Was the purported 1968 standard for encoding ASCII on punched cards ever used?

Multics came close. Multics used ASCII for its usual text representation, and could punch and read it from cards. There were only six differences between the Multics card code and the ANSI standard. ...
John Doty's user avatar
  • 2,789
12 votes

Why were programs entered on punch cards instead of paper tapes?

To add one more dimension to the answers already given: cards are easier to handle, whether by operators, or in a cafeteria (user self-service) system. A high-speed card reader has an input hopper and ...
dave's user avatar
  • 35.7k
12 votes

Was any indentation-sensitive language ever used with a teletype or punch cards?

Historically, was any indentation-based language ever used with pre-screen code entry technology like teletype or punch cards? Of course, even the very first: Assembler And it still does: Any ...
Raffzahn's user avatar
  • 224k
11 votes
Accepted

Which programming systems used object files on punch cards?

It wasn't just a Soviet thing: … This time I decided to look closely at the program deck. By now I knew just about everything there was to know about the source deck. The program deck was ...
scruss's user avatar
  • 21.7k

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