telecommunications some very large and very small values

In telecommunications some very large and very small values are used. To make writing of these numbers easier use is made of a prefix. The prefix gives a value with which the value must be multiplied.

Some prefixes are also used in digital communications and computer technology but they have a slightly different value because they are based on a power of 2.

Prefix	Analog value	Digital value
p (pico)	10-12	-
n (nano)	10-9	-
µ (micro)	10-6	-
m (milli)	10-3	-
k (kilo)	103 (1000)	210 (1024)
M (mega)	106 (1,000,000)	220 (1,048,576)
G (Giga)	109 (1,000,000,000)	230 (1,073,741,824)
T (Tera)	1012 (1,000,000,000,000)	240 (1,099,511,627,776)

An analogue signal is a signal that varies continuously in both time and amplitude (strength). The variation in time is commonly expressed in the frequency (tone) or frequencies the signal is composed of. The unit of measurement is the Hertz, or cycles per second.
An analogue signal can be e.g. an electric signal that comes out of a microphone.
The opposite of an analogue signal is a digital signal, which is discrete in both time and amplitude. An Analog-Digital Convertor (ADC) is needed to convert an analogue signal to a digital signal.
The term analogue is also used to refer to devices or circuits which handle analogue signals. The output of an analogue device varies as a continuous function of the input.
The first generation mobile communications systems (1G) were analog.

Giga

Giga is a prefix that is used as a multiplier. The prefix giga is written as a uppercase "G" in front of the measure.

In the "analog" world Giga represents the numeric value of 1,000,000,000 (a thousand million or 10⁹); such as a frequency of 5 GHz, which is 5,000,000,000 Hz.

When used in the digital world, Giga represents the numeric value 1,073,741,824 (1024×1024×1024 or 2³⁰; e.g. a bit rate of 8 Gbit/s, which is a rate of 8,589,934,592 bits per second).

Kilo

Kilo is a prefix that is used as a multiplier. In the "analog" world, kilo represents the numeric value of 1000 (10³); such as a frequency of 20 kHz, which is 20,000 Hz.

When used in the digital world, kilo represents the numeric value 1024 (which is 2¹⁰); e.g. a bit rate of 8 Kbit/s, which is a rate of 8192 bits per second.

In the analogue world the prefix is written as a lowercase "k", whereas in the digital world the uppercase "K" is used.

Mega

Mega is a prefix that is used as a multiplier. The prefix mega is written as a uppercase "M" in front of the measure.

In the "analog" world Mega represents the numeric value of 1,000,000 (a million or 10⁶); such as a frequency of 90 MHz, which is 90,000,000 Hz.

When used in the digital world, Mega represents the numeric value 1,048,576 (1024×1024 or 2²⁰; e.g. a bit rate of 8 Mbit/s, which is a rate of 8,388,608 bits per second).

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