Hard+Disk+Drive

= = toc = = =**Purpose**= Purpose //What is the fundamental purpose of the device?//

The purpose of this device is to store digital information from a computer, cameras. Hard disk drives, more commonly known as just hard drives, or HDD are in every single computer you've ever been on. Every time you save a document on Microsoft Word, or upload your pictures from your digital camera onto your computer, all of that information is stored onto your hard drive. There are VCR-type devices and camcorders that have the ability to use hard disks instead of tape to record.

Energy
//What energy transformations are seen in its operation?//

Energy seen in a hard drive is the electrical energy making the motor spin the disk. For a hard drive to work, you need electricity, which you plug into an outlet, which then gives the whole computer power, which powers the hard drive, motherboard, and the fan. This energy then makes the motor work which spins the disk which allows the hard drive to run and allow your computer to download, and store games, files, and anything you'd like to save on your hard-drive.

Controls
//What sensors/controls are designed into the device?//

Sensors or controls that are built into the Hard Drive are the arm, the platter, and the electronic board. On the bottom side of the hard drive, there is an electronic board that reads the Hard Drive for the last saves, the arm also writes on the Hard Drive, also meaning the arm saves. The arm has many functions, but it also controls the motor that spins the Hard Drive. The platter is where all of your information is stored, and where the arm writes all of the saved data onto the Hard Drive. They are stored in separate disks that are stacked on top of each other, to enable the user of the computer to have a lot of saving space. Last, the arm is what sends and receives information to different sectors of the platter using the motor at incredibly fast speeds.

**Materials** //What material(s) are essential to the device?//

A hard drive has an aluminum case that surrounds it's inner parts to protect the Hard Drive from failure. An external material that is essential to the hard drive is the motherboard, as this is what the hard drive feeds its saved information onto to allow maximum storage (saved data). The monitor is an essential part to a computer because having a monitor would complete the whole setup and the monitor allows you to navigate through your whole computer and view your saved data.

**Science** //What scientific principle is central to its operation?//

Scientific principles that are central to its operation are the motor, to spin the disk or platter; and the head, to send and receive information through the platter. The next three biggest scientific principles are the monitor, the mother board, and the outlet. The monitor is the biggest, most essential part of the computer because the monitor allows you to navigate what you have saved on your computer. The motherboard is like the "god part" of the computer. The motherboard allows all of the parts to interact with each other and communicate with one another allowing your computer to run at max speed.

**Design** //What does a typical device look like?//

Hard Drives Disks are a circle, but the whole hard-drive is in a rectangular form, with a metallic disk that takes up over half of the size. This typically spins at 3,600; 7,200; or 10,000 rpm's. The abbreviation "rpm" stands for revolutions per minute. RPM which is the amount of revolutions the disk, also known as the platter, how many times that spins in a minute. Another main part of the hard drive is the arm. The arm transmits information to different parts of the disk in order to save and continue for the hard drive to allow saves.

If you've ever seen a hard drive, you know that the platter and the arm are covered by a metal plate. This is to prevent dust or dirt from getting into the hard drive and causing failure. With the cover removed from the disk, you take the chance of ruining the hard drive

Evolution
//What changes have there been (or could there be) in this device?//

Hard Drives were invented in the 1950's. They were much bigger than they are now and they could only hold a few megabytes of data. Now you may not know what megabytes are, but if you have an iPod or a mp3 player, you should know that megabytes are a measurement of how much storage there is available on your device/machine. The base measurement of space that a hard drive can hold are called bytes. For every 1,000 bytes, that is equal to 1 kilobyte, for every 1,000 kilobytes, that is equal to 1 megabyte, and for every 1,000 megabytes that is equal to 1 gigabyte.

Hard drives have been expanding in the amount of space that they contain. Currently, there are some hard drives that can hold up to a Terabyte of space, which is equal to 1,000 gigabytes! In the future, there could definitely be some major changes in the disk capacity of hard drives and the ability they can process the saved data, load data faster and have the ability to move it quicker. The reliability in hard drives could also increase so that they can store their information for longer periods of time and have longer life spans.

**Related Devices**

Competitors
//What other devices serve a similar purpose?//

In my opinion I think that CD's when you create or burn them on your computer relate to hard drives in the biggest way because the way that hard drives save data is with the arm burning an encrypted code onto the disk, and that is the way computers burn CD's in your computer, with an arm writing the codes onto the CD.

Partners
//What other devices work in conjunction with this device?//

Devices that work in conjunction with the hard drive would be other parts of the computer that contribute to every part of the hard drive and monitor to work. The keyboard, for example, would be a partner because when you use the keyboard, it sends information to the hard drive, which then allows you to type and save that word document you're typing. Another partner would be the motherboard. Every computer needs and has a motherboard, since almost every computer part is connected to it, including the hard drive. The monitor would be a big part because all of the information stored on your hard drive is displayed on your monitor which helps you navigate through your hard drive. Hard drives wouldn't have too much of a use without something to view the stored information on.

Siblings
//What other devices use the same scientific principle?//

Some other devices that serve the same scientific principle are CD's. CD's also store information digitally, and are common with Hard Drive's because they also are written with the arm of a computer when you "burn" a CD. http://www.ehow.com/video_4767082_what-definition-hard-disk-drive.html **Sources:**
 * [|How Stuff Works - "How Hard Disks Work"]
 * [|Hard Drive Disk Wikipedia]

http://video.google.com/videoplay?docid=-744683267829297106#docid=-4902092949486919331 This video will explain to you how a hard drive can fail. http://www.ehow.com/video_4767082_what-definition-hard-disk-drive.html ** This video will explain what the definition and purpose of a hard disk drive is.
 * Videos: