What is a hard drive? How does a hard drive affect PC performance?

A hard drive is a non-removable, permanent storage media used on a modern PC. It is usually constructed of several metal plates, housed in an environmentally-insulating case, which is directly attached to the motherboard via a socket or a cable. These devices store information by physically altering the surface of the hard drive. The information is read by a stylus, similar to the ones seen on an old record player, under which the drive “platters” spin at a remarkably high rate. The most important factors for a hard drive are size and speed.

Hard drive size increases a great deal every year. It wasn’t too long ago that a 10GB hard drive was a very big storage device. Today, hard drives measured in terabytes are available. This trend will likely continue until either the commonly-used configuration of the hard drive is fundamentally altered—and this is starting to happen, to some degree—or until the entire means by which information is permanently stored is completely redesigned. For the moment, every year means bigger hard drives and programs that require more space to operate.

The hard drive is the location where all of the computer’s basic instructions and information are stored. The operating system is located on the hard drive. All of the user’s files that have not been stored to a removable media are stored on the hard drive. This component, along with the CPU and the RAM, is one of the basic pieces of technology that defines a computer.

Increasing the quality and capacity of a hard drive can very much increase the speed of a computer. Part of a hard drive is used for what’s called “virtual memory”. Other parts of the hard drive are used for temporarily storing data while a computer is running tasks. A full hard drive can slow a computer down by compromising the computer’s ability to use such resources. Installing a new hard drive will oftentimes alleviate such problems. Increasing the storage space, of course, means that more files may be saved to the hard drive without reducing the space to the point that it compromises performance.

Hard drive spin rates also affect performance. This is measured in RPM, rotations per minute. The hard drive retrieves information via the spinning discs, thus, the faster those discs spin the more information can be retrieved in a given amount of time. Hard drives spin incredibly fast, with high-performance models frequently approaching 10,000 RPMs. This statistic will generally be given as one of the base descriptions of any hard drive, though users tend to pay less attention to it than they should.

There are other ways of speeding up performance by adding multiple hard drives and using different types of what are called “RAID” configurations. In a performance RAID, both hard drives work off of one another, increasing the amount of information they can retrieve and allowing for smoother performance. This configuration is popular with gamers who need the fastest possible performance.