digital

Being ‘digital’ is in contrast to being ‘analogue’.
Analogue means to resemble something else, as in an analogy.
In terms of technology, analogue is often displayed through gauges and dials. A traditional thermometer is an analogue display in that the rising or falling mercury in the thermometer gives a direct measurement of the temperature. Similarly, the traditional speedometer dial in a motor car rises as the car accelerates and falls as the car slows down. A watch with hands is also an analogue display.
In contrast, digital refers to a display by digits or numbers and derives from the binary (meaning ‘two’) states of electronic switches. A binary form is either ‘on’ or ‘off’.
Digital displays are usually shown as a set of numbers, as in a digital watch telling the time as ‘12:21’ or as a set of bar graphs often used in stereos.
The connection between digital and analogue is a significant one in terms of the shift from mechanical forms to electronic technologies. An analogue display reflects the variable movement of the mechancial device whereas a digital display reflects the on-off nature of the electronic device. A digital device merely switches on and off so quickly that it appears to be a variable in nature.
In music, the old vinyl long playing records were analogue recordings with each sound mirrored in the groove of the record. The needle literally moved with the flow of the music. Today, Compact Discs are digitally recorded on the plastic disc, which means a series of very small on-off bumps are cut into the disc. In computer terms, these are called bits.
Examples: digital camera, digital watch, digital watermark, personal digital assistant