Data acquisition involves measuring the values of physical quantities such as temperature or voltage as a function of either time or some independent system parameter.

In modern practice, an appropriate transducer generates an electrical signal corresponding to the phenomenon to be measured. Signal-conditioning electronics then convert the signal into a form that can be read out by analog-to-digital converters (ADCs), which are in turn recorded on a computer. In cases where a value must be recorded as a fuction of an independent parameter, the computer may use digital-to-analog converters (DACs) to provide the needed stimulus.

Data acquisition is commonly abbreviated as “DAQ”.