Data Logger

Data loggers are devices that record date over time. Data loggers are used in the medical field to monitor and record a variety of inputs, such as liquid temperature, the pressure of liquids or gases, humidity, and even voltage and current. Medical applications include the monitoring and recording of environmental conditions for the safe storage of vaccines and medicines as well as recording health data over time (such as with Holter monitors). While they can be used in conjunction with a computer, data loggers primarily operate independently as stand-alone devices.

• Data Logger (Wikipedia)