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63

Forty years ago, a 7MB file would be unheard of, at least in contexts where floppies would be the only available means of transferring it. (Tapes were commonly used for large transfers on minis and mainframes.) In slightly more recent times (even thirty-odd years ago, and then as long as floppies were still useful), we used archiving tools with support for ...


49

For the simple reason that until relatively recently, it was very difficult to make a rewritable optical medium, but it was easy to make a rewritable magnetic medium. Magnetic tape as a recording medium has been a practical technology since the late 1930s, predating the digital computer. For comparison, CD-RW was introduced only in 1997, more than a decade ...


34

Gameboy games use a CR2025 battery which over the years eventually dies stopping games from saving and causing previously saved games to disappear. Note however while the game is powered you can still save, however once you power down the save will be gone. In order to replace the battery you must open up the cartridge with a 3.8mm screwdriver security bit. ...


34

As far as I remember, this wasn't a CD, but (supposed to be) a Laserdisc, and he was using a Philips player (the movie contained several Philips machines). Laserdiscs were available in different sizes between 12 cm, which is like a CD and up to 30 cm (LP size). In a technical way, the movie screwed up, as Laserdisks were neither digital (they used an ...


27

As well as splitting across multiple floppy disks, there were several cabled communication options available ranging from your basic serial cables and sending data over via X/Y/ZMODEM or Kermit, but there was also specialized parallel cables (like printer cables) that could be used that facilitated even faster transfers. I think "LapLink" was a such a ...


26

Write speed and endurance. Optical drive technology has been much slower to write to than magnetic Hard Disk Drives (HDDs). The erasable optical technologies that made it to mass market were much slower in write time than HDDs and in erase time. Their life before failure was in the 100's of erases. Optical drive use declined with the advent of USB flash ...


25

40 years ago - 1978 - there was no home/hobbyist/small office computing to speak of. Maybe a few hundred people altogether. So you must be talking about commercial/industrial computing. For large files we used 1/2" mag tape: You've seen drives like this in older movies: These tapes could hold one hell of a lot of data: Maybe 50Mb. (Really high ...


22

Yes, the IBM 1360 used it. The wikipedia page suggests that it could store 0.5 terabits (64 GiB) of information. https://en.wikipedia.org/wiki/IBM_1360 Fascinating design.


19

It IS used in at least two places even today: QR codes. There is the possibility of the print media carrying it having been prepared involving photographic methods. Digital sound in movie theaters, when projecting from actual film - even quite modern standards like Sony SDDS, Dolby Digital define how the sound can be carried as digital data encoded ...


17

Gameboy games use CR2025 battery, which will die and take all the data with it: It's lost for good. Saved games back in those days were preserved through the use of a battery right in the game pack, not stored on the gaming device itself like it is today. And when that battery dies, so does the saves with it. It's not about corruption of the save or ...


15

Do have a 7 MiB file, you would need a HD at least that size. In reality even a manyfold thereof, as usually one won't have a HD with just one file. Now, in the real early times, lets say 70s, home users wouldn't have disks at all - not even floppies, and professional users with minis would use disk packs (exchangeable hard disks) and maybe fixed disks of ...


15

That is a Philips VP415 LV-ROM player.


13

I don't remember what the memory density was compared to today's SD cards. No, today's flash offers a way (several magnitudes) denser storage, but it is also way less reliable. What happened to bubble memory - is it still being sold? It might be still around. Today bubble memory is a rather special niche market with most uses in military and space ...


13

Magnetic Bubble Memory (MBM) was a technology that never found a sustained market, and was only briefly in vogue a couple of times in the 1970s and 1980s when market and technical issues hit other storage technologies. While MBM is non-volatile and fairly rugged, it has a few show-stopping disadvantages, including: It needs to be heated to over 30 °C ...


11

Your timescales are out. Floppies might have just existed 40 years ago, but your average office worker never saw one. More to the point, office workers didn't pass machine-readable data around the office to each other, the only equipment they had that could read the data was a shared mainframe, so they would both access the same copy. From Gio Wiederhold, ...


10

The story is told in this 1988 usenet post by Paul Homchick: Some time went by and it was a CP/M world, and diskettes were bigger. In 1981 Richard Greenlaw released SQ and USQ, based on Huffman encoding and written in BDS C. This was the first popular compression technique. Greenlaw gave away the binaries and source code. <...> By 1983 it ...


10

The short answer is MS-DOS 3.3. According to the MS-DOS Encyclopedia, MS-DOS 2.0 to 3.2 (included) only supported one MS-DOS partition per partitioned device (hard drive basically). (Before MS-DOS 2.0, hard drives weren’t supported at all.) MS-DOS 3.3 introduced support for multiple partitions per device, albeit still limited to a single primary partition ...


10

Sprocket-driven 35 mm photographic film stock was used to store data in the British Elliott 803 computer. It wasn't used optically, however: it was coated with iron oxide and used as magnetic media.


10

ZIP drives come with many different types of interfaces. The most prevalent were: Internal ATAPI version, most commonly installed in PCs. (An IDE version also existed, but was rather uncommon.) External Parallel port version, most commonly connected to PCs. Internal SCSI version, most commonly installed in early Macs. External SCSI version, most commonly ...


10

What prevented optical drives from being used as the dominant secondary storage like the magnetic disk drives in PCs? Speed Density Complexity Technological advantage of Disks Reliability Did I mention speed and density? Even a Blue Ray does only pack 25 GiB of data on a (5.25) side. Actual HD do up to 700 GiB per (3.5) side. At times various ways of ...


9

It appears that there are several versions of both DoubleSpace and DriveSpace. Information about each version as I find get it will be posted in this answer. DoubleSpace DoubleSpace uses MRCI, which uses "a variant of Lempel-Ziv encoding".[2] A non-technical explanation of the DoubleSpace compression algorithm: DoubleSpace first identifies the repeated ...


9

The difference between 360KB and 500KB is not entirely due to space between sectors. A lot of the difference is due to clock sync bits, sector identification markers, checksum/ECC bits, etc. Keep this in mind otherwise comparisons are meaningless. Taking the DEC RP03 disk pack drive as an example of an "early hard disk", I took a look at the maintenance ...


9

Update As of the release of ProDOS 2.5 alpha#5, up to 37 drives are supported. This is done by increasing the number of mapped drives per slot from 2 to 8, which would theoretically allow 56 drives. However, there is only enough reserved memory for the table of unit numbers to hold up to 37 entries. ProDOS, being an 8-bit OS designed to run in 64K, uses ...


9

It doesn’t need to be loud, it needs to be unshielded. Many speakers produced in the last 20-30 years are shielded, to avoid their magnets affecting surrounding objects — particularly CRTs (you don’t want your speakers changing the colours on your retro TV screen), but as a side-effect, magnetic media too. If you have unshielded speakers with strong enough ...


8

DECtape was used that way; it was wide (0.750 inch?) magnetic tape, on very small reels, so it didn't take forever to find a sector. PDP-8 and PDP-11 systems from Digital Equipment were the likely systems sporting DECtape drives. The tape was fully redundant, took a LOT of wear without losing data, and that made it suitable for such system-program use. ...


8

Experimentally verified data retention duration: 0 seconds. Because you asked and I was curious too, I have just cut an ED notch in one of my old HD disks (to trick the drive into thinking it were an ED disk) and tried to format it in my ED disk drive set on my Sinclair QL - It wouldn't even format. The drives have no problem whatsoever in handling both ED ...


8

Which OS? Using a Unix or variant, we used cpio, which would detect end of media (tape or floppy) and prompt to replace and continue onto (or from) another volume. The media was just treated as a sequence of blocks of data. If using MSDOS, there was BACKUP and RESTORE commands that spanned floppies but I’m not sure if they were in DOS exactly 40 years ...


8

There were many optical readers used for punched paper tape; so in some sense holes in paper was treated as a photographic record of the dots on the screen. The Colossus machine at Bletchley Park used optical tape readers at very high speed and this pre-dated the Williams Tube. https://youtu.be/xeDyF4HviDE


7

Not exactly what you expect, but the Zuse Z1 and its successors used photographic film as punched tape. This design decision was made because Konrad Zuse was able to find large amounts of old film rolls on a nearby scrapyard, removing the need to make his own tape.


6

40 years takes us back to the dawn of "Personal Computing". In June 1978 Apple released the Disk II for its Apple II computer. It was based on the Shugart SA-400, the first widely available 5.25" drive. Prior to that there were only 8" floppy drives. That would take up quite a bit of desk space. There weren't many files larger than a disk at that time ...


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