Digital multimeters have developed slowly through history. Early multimeters used a magnet to deflect the dial of the needle, the same as a classic galvanometer; modern ones use a digital display provided by an LCD or VFD (Vacuum fluorescent display).
Analog multimeters are not hard to find on the used market, but they are less accurate because both zeroing and accurate readings from the instrument panel are prone to bias.
Some analog multimeters use vacuum tubes to amplify the input signal. Multimeters of this design are also called vacuum tube voltmeters (VTVM, Vacuum Tube Volt Meters) or vacuum tube multimeters (VTMM, Vacuum Tube Multimeters).
Modern multimeters are all digital and are referred to exclusively as digital multimeters (DMM, Digital MultiMeter). In this device, the signal to be measured is converted into a digital voltage and amplified by a digital preamplifier, and then the value is displayed directly on the digital display; this avoids the deviation caused by parallax in the reading.
Likewise, better circuitry and electronics improve measurement accuracy. Older analog meters had a basic accuracy of between 5% and 10%, modern portable DMMs can achieve ±0.025%, and bench devices are even more accurate to parts per million.
