Image Image Image Image Image Image Image Image Image Image

fosfor gadgets | November 18, 2018

Scroll to top


One Comment

History of data storage

Magnetic tape

Did you know that it would take around 6 000 floppy disks to store one DVD – or 4 500 compact cassettes, with a playback time of 280 days? Here’s a brief look into the history of data storage.

Punch cards

90 column punch card punched in 1972 The oldest known form of data storage is from 1725 and was done by Basile Bouchon when he used a perforated paper loop to store patterns that were to be used on cloth.

But the first real patent for some kind of data storage is dated back in 23 Sep 1884 by Herman Hollerith (pdf) – an invention that was used for nearly 100 years until the mid 1970s.

Here’s an example of how a typical punch card could look like, it’s a 90 column card punched in 1972. As you can see the amount of data that could be stored on a punch card wasn’t much, and their primary use wasn’t to store data, it was to store settings for different machines.

90 column punch card []

Punched tape

Fanfold paper tape

The first known use of the paper tape was back in 1846 by Alexander Bain – the inventor of the fax machine and the electric printing telegraph. Each row on the tape represents one character, but since you easily could create a fanfold you could store signigicantly more data using the punched tape compared to the punch cards.

Paper tape [Wikipedia]

Selectron tubes

 RCA Selectron 1024-bit Selectron prototype No. 4124-3 In 1946 RCA started the development of the Selectron tube. It was an early form of computer memory and the largest selectron tube measured 10 inches and could store 4096 bits. As these tubes were very expensive, they were very short-lived on the market.

The RCA Selectron 1024-bit prototype []

Magnetic tape

Magnetic tape

In the 1950s magnetic tapes was first used by IBM to store data on magnetic tape. Since one roll of magnetic tape could store as much data as 10 000 punch cards it became an instant success and became the most popular way of storing computer data until the mid 1980s.

Magnetic tape [Wikipedia]

Compact Cassette

Magnetic tape

The Compact Cassette is of course one kind of magnetic tape but since so many of us have used them, it deserves a special section. The Compact Cassette was introduced by Philips in 1963 but it wasn’t until the 1970s it became popular. Computers like the ZX Spectrum, the Commodore 64 and the Amstrad CPC used the cassettes to store data. A standard 90 minutes Compact cassette could store around 700kB to 1MB of data on each side of the tape. How about buying 4500 compact cassettes and create a backup of your favorite DVD – it would only take 281 days to restore the data, hehe.

The magnetic drum

IBM 650 magnetic drum

The magnetic drum was a 16 inch long drum spun that did 12,500 revolutions per minute. It was used to give the IBM 650 computer about 10 000 characters of main memory.

The magnetic drum []

The floppy disk

3.5 inch floppy disk

In 1969 the first floppy disk was introduced. It was a read-only 8 inch disk that could store 80kB of data. 4 years later, in 1973, the a similar floppy disk with the same size could store 256kB of data plus it was possible to write new data again and again. Since then the trend has been the same – smaller floppy disks that could store more data. In the late 1990s you could get ahold of 3 inch disks that could store 250 MB of data.

Floppy disks [wikipedia]

World’s first hard drive

1956: IBM 305 RAMAC Computer with Disk Drive

IBM unveiled the 305 RAMAC on September 13th, 1956. The computer was nothing but a revolution since it could store up to 4.4MB of data (5 million characters) – an enormous amount of data back then. The data was stored on fifty 24 inch magnetical disks. More than 1000 systems were built and the production ended in 1961. IBM leased the computers for $3 200 per month.

IBM 305 RAMAC []

The hard drive

Hitachi Deskstar 7K500 - the first half terabyte hard drive.

The hard drive is still a product that is under constant development. The Hitachi Deskstar 7K500 that you can see on the image above is the first hard disk drive that can store 500 GB of data – or approxmiately 120 000 times more data than the world’s first hard drive IBM 305 RAMAC. The trend is crystal clear; for each year we get cheaper drives that can store more data faster.

The Laserdisc

A laserdisc to the left, a DVD to the right

In 1958 the Laserdisc technology was invented, but it wasn’t until 1972 that the first videodisc was demonstrated in public. 6 years later, in 1978, it was available on the market. It wasn’t possible to store data on the discs, but they could store video and image data with a significantly higher quality than tecnniques like VHS.

The Laserdisc [wikipedia]

The compact disc

The compact disc

The compact disc originates from the laser disc, but it’s much smaller (and stores less data). It was developed in a co-operation between SONY and Philips back in 1979 and the Compact Disc reached the market late in 1982. A typical CD of today can store 700 MB of data.

Compact disc [wikipedia]



A DVD (Digital Versatile Disc or Digital Video Disc) is basically a CD that uses a different kind of laser technology. The laser’s wavelength uses 780nm infrared light (standard CD use 625nm to 650nm red light) which makes it possible to store more data on the same amount of space. A dual layer DVD can store 8.5GB of data.

DVD [wikipedia]

The Future?

Holographic Versatile Disc

There’s a lot of modern data storage media like memory cards we haven’t mentioned here, but in the near future we are about to experience the launch of Blu-Ray and HD DVD – two competing formats which basically just is another version of the compact disc that can store even more data thanks to the blue-violet laser technology. It will be interesting to see which format wins, but Blu-Ray seems to be the gaining in popularity.

But it’s when we start to look beyond these formats things are starting to get interesting. What would you say about having a Holographic Versatile Disc that could store 160 times more data than a Blu-Ray disc. 3.9 TB of data on one disc – or approximately 4,600 to 11,900 hours of video using MPEG4 encoding – or would you rather spend a fortune on a couple of billion punch cards?

Holographic Versatile Disc

Store 1 DVD on…

Store 1 8.4GB DVD on...

Yeah, that’s right. It would take approximately 90 million punch cards to be able to store one 8.4GB DVD, or 6 000 floppys, or 4 500 compact cassettes ( it would only take 281 days to restore the data, hehe) – or if we would turn it the other way around, it would take 0.2% of a 3.9TB Holographic disc…

One comment on “History of data storage

  1. Just to let you know, in case you want to update your article, laser disks did not store digital data but the analogue video and audio signal. It wasn’t digital but more like vinyl, with the information being read by a laser instead of a needle.

Leave a Reply

Your email address will not be published.

HTML tags are not allowed.