Analogue/Digital Conversion

The word analogue refers to a continuous range of values. In the context of information processing, it means data is represented by physical quantities that change smoothly over time.
Digital data, on the other hand, is characterised by discrete values. In digital systems, information is typically represented using binary (0s and 1s).

Analogue data is inherently noisy since it encounters noise from the environment (like temperature or magnetic fields). This can alter the information.
Digital data is less susceptible to noise as it only has two states: 0 and 1. Even if noise changes these states slightly, the digital circuitry will interpret them correctly.

The conversion of analogue signals to digital is called digitisation. This process allows analogue data to be stored and processed by digital devices.
Digitisation involves two steps: sampling and quantisation.
Sampling involves taking frequent measurements of the analogue signal at uniform time intervals.
Quantisation is the method of mapping the measured analogue samples to a series of discrete digital values.

The process of converting digital signals back into analogue is known as Digital to Analogue Conversion (DAC). This process takes a series of binary numbers and produces a continuous analogue signal.
DAC is important in multimedia applications where digital data needs to be output as sound or video, such as playing audio files or streaming video services.

The transformation of analogue signals to digital allows for the storing, processing, and transmission of data in digital form without losing the original information.
Digital data can be encrypted, thus providing a higher level of security than analogue data.
Digital copies of data can be made without any degradation of quality, unlike analogue copies which are subject to loss and distortion.

Analogue to Digital Conversion (ADC) and DAC are crucial in telecommunications applications, enabling the transmission and reception of data over digital networks.
They play a vital role in audio and video systems, like television broadcasting, where audio and video need to be converted between analogue and digital formats.
They are also an important component of computing devices, where data is processed digitally but often interfaced with the real (analogue) world.