An Alternative Definition for IQR. In some texts, the interquartile range is defined differently. It is defined as the difference between the largest and smallest values in the middle 50% of a set of data. To compute an interquartile range using this definition, first remove observations from the lower quartile.
A hard drive is a device used to store data in a semipermanent state on your computer. Computer memory is a series of small packets of data called bits. Each bit is a 1 or a 0, and each bit is stored as a small magnetic charge on the hard drive. A read/write head moves over the hard drive to retrieve or rewrite the bits as needed.
The hard disk drive is the main, and usually largest, data storage hardware device in a computer. The operating system, software titles, and most other files are stored in the hard disk drive. The hard drive is sometimes referred to as the C drive due to the fact that Microsoft Windows designates the C drive letter to the primary partition on the primary hard drive in a computer by default. While this is not a technically correct term to use, it is still common. 1  For example, some computers have multiple drive letters (e.g. C, D, E) representing areas across one or more hard drives. 2  These settings vary from drive to drive, so check with your hard drive manufacturer for details.