User:HamishLight

== The Advances in Computer Memory And Data Storage

A great advancement in computing history, The Magnetic Drum Memory could hold up to 10KBs, or 0.00001GBs in its first version, which was remarkably large. The magnetic Drum Memory was invented in Austria, 1932, but the concept was only popular in the 1950s and 1960s...

Magnetic Tape was first used back in 1951 for storage, and was called 'UNIVERSO'. UNIVERSO was the main Binary Code device on the UNIVAC I computer and could transfer 7,200 characters per second.

A Hard Drive is based on Magnetic storage and Magnetic storage depends on magnets to magnetize other materials so that they can hold their magnetisation until told otherwise when exposed to another magnetic field. now looking back at computers, you may already know that computers transvert data into 1s&0s (binary code), and materials can be magnetised in two different ways, by using a north end, and a south end. Okay, but what does this mean? Well, let me explain:

This means that computers can transfer the data from 1s&0s, to materials magnetised by north and south poles, and because we can control that, and it still equals the binary code; even though its a different form... we can store our data by using a directed electro-magnet to magnetize our materials (which now holds the data). Did everybody get that?

One other computer data storage device that holds over 2000 bits is The Selectron Tube. This big and spiky device only held around a 5,000,000th of what most USBs can hold today, but that wasn't why it was neve a money making machine; it was actually a fair advancement for it's time. the reason it never went viral was because of how expensive it was, meaning it suffered production problems and never became a success.

Another invention I will talk about is the Punch Card: These were first used for holding programming and slipped into Mechanical Textile Looms in 1725. Mechanized Looms were machines that weaved fabric or clothing. Computers punched data and programming into these slips of cardboard to show on other devices (in data) and machines (in programming). Although they were useful, they could not hold real-life-graphic movies, special effects or DIGATAL games ect. These cards died out in 1970.

Much like Punch cards, Punched Tape originated in the Textile business aroundthe 1840s, but unlike Punch Cards, Punched Tape could obtain data and out-put it into different devices, other than just the one. Every row (row=the width,(going across)not length) on the Punched Tape was read as a character, making a sentence or so from the computers information.

The device that came before the CD or DVD we know today was called a Laserdisc, it could hold up to an hour of Audio and Video on each side and was 30cm in diameter.Now how these work is because of these microscopic bumbs that give out a different image because of how the laser reads it when it goes out. Born in market late 1978, the first of these discs had entirely analog content, which means instead of the lasers reading the changes in binary, they read in all different ways because the bumbs on the alliminium were all sized and shaped differently, so there were much more complex out-puts than what we have today, making an incredible picture with great audio and an impressive design on the source (The Laser Disc). Nearly 20 years after the original release, The Laserdisc addapted, in the late 90s some would have for example: 5.1 Digital surround sound. Additionally, before The Invention of The Super Audio DVD in the mid 2000s, Laserdisc used to play an abundance of different sound tracks.

Furthermore, The Laserdisc had a much longer lifespan than its competition, as it was not optical, magnetic and degraded at a much slower rate than any of its competitors, making it superiour. As well as this, The Laserdisc had efficent and easy chapter selections way before its time from the late 1980s, making it one of the best movie-players of all time, but we don't see many today; this is because VHRs were much cheaper than them in countries like Australia and America. So these went out of fashion because no one would pay double for the same movie that you would have to flip half-way through, or have 2 discs for (if it was over 2 hours long),and even though they soon made the disc able to read the other side without having to flip it manualy, it was far too late to save Laserdisc. (sad music)

The flexible Floppy Disk was at its most popular in the mid-1970s to the late 1990s. The first floppy disks were 20cms in diameter in the first versions, but eventually got down to 8.9cm formats. The first floppy disk, introduced in 1971, had a capacity of 0.00008GBs, and could only be examined -the original data was burnt in buy first creation-. A read-write version came a year later. In the image of the floppy disk, you might notice some semi-circle holes down the bottom, those are called Relief Notches, these exist for the sole purpose of minimisation in bending around the reading area, also on the disk there is an index hole, this is located to the side of the hole in the middle, now, not all of these disks have these, the reason these are there is because being monitored by a sensor, it could tell the drive exactly where the disk was rotation wise. Far off to the side is the Write bProtect Notch (toggleable), if the sensor monitoring this, found that it was open, you were allowed to write.

Now going inside the disc: The actual data is stored in a big bulk in the middle all the way around; the first track would be on the outside edge, and working down to the 40th track, that is in the inner edge of this section. Inside the disc drive is the a Stepper Motor is used to move the read head back and forth to access the different tracks I just mentioned. Some of these disc drives have a sensor that tells it where the read head is, but the ones that don't send a command to the read head to go to the first track, it does this 40 times so that the read head will certainly make it back. More about how the data is stored, the drive divides the disc up into many sections, as shown in the picture. This picture makes efficent use of the disk by having the same area in each section, unlike some that just divide every track by the same line; Due to this change in unique patterns for every discs, some brands of disc drives could not read others. When advancements started flowing, these disc designers made a disc and a drive that could read both sides, storing twice the data, but the only problem was that it still only had 1 write protect Notch, so you were only able to write on one side, because when you flip it over it would be on the opposite side. This problem was noticed and easily overcome by just making another hole.

Magnetic Tape was first used back in 1951 for storage, and was called 'UNIVERSO'. UNIVERSO was the main Binary Code device on the UNIVAC I computer and could transfer 7,200 characters per second.

Websites: https://www.youtube.com/watch?v=f3BNHhfTsvk https://royal.pingdom.com/2008/04/08/the-history-of-computer-data-storage-in-pictures/ https://www.youtube.com/watch?v=nU4FTNv-ldc https://www.youtube.com/watch?v=EHRc-QMoUE4 Books: Electronics by Roland Worcester, published 1970.