How Hard Drives Work
The hard drive (also called hard disk, or hard disk drive) stores all the data that is saved on your computer. Every file you save, program you download, or setting you select has a place on your hard drive. The Windows operating system resides on your hard drive too. Without your hard drive, not only would you not be able to save any data, you wouldn’t be able to operate your PC. But how does a hard drive work?
Hard drives are composed of platters which rotate at high speeds. These platters are similar to compact disks or records, spinning quickly to transfer information. A hard drive does not just have one, but several platters, each with their own head unit. Unlike CD and records, the platters are not removable, but information can be written, erased and re-written to them many times.
The read/write head, the component which picks up the information on the platter, does not actually touch the platter, but hovers just above it. The head unit does not sit on a neck, but rather on an arm.
The platters themselves store information not through grooves, but through their magnetic surface. The allows for data to be rewritten, and for much faster data pickup times. Not only that, but a computer does not simply read a planner in one direction - it jumps around from place to place, as various programs and documents are accessed by the user. The spinning platter typically rotates between 5,000 and 10,000 times per minute on the average desktop PC. Laptops are on the slower range of RPMs, usually closer to 5,000.
Your files, however, can not simply be copied to a platter. The information must be recorded to the platter in a way which can be quickly transferred and understood. Here is where binary code, bits, and bytes comes to play. Binary simply means that all information is conveyed through 1s and 0s (there are only two options, 1 and 0, hence the bi- prefix). These two symbols are how everything on your computer is recorded, be it music, text, or video. Of course, it takes thousands and thousands of these symbols for complex files such as photographs.
Each symbol, either 1 or 0, is called a bit. 110 would be three bits, and 0 would only be one bit. Computer programmers have also taken to referring to bits in groups of eight. A clump of eight bits is called a byte. 11010001 is one byte (it’s eight bits). 0100111100000101 is two bytes (it’s sixteen bits).
So, every time you click Save, the information travels through your computer to your hard drive, where the head rapidly writes the information (in binary) to the quickly spinning platter. Whenever you want to access a file, the same happens in reverse: the read/write head picks up the binary code on the spinning platter, and that information is send through your computer and converted into a format that we can understand (such as text, or a picture).
To learn more about how data recovery brings back deleted files from your hard drive, check out this article on how data recovery works.
Want to learn more about the technical side of hard drives? Check out this Wikipedia article: http://en.wikipedia.org/wiki/Hard_disk_drive
