1. A data logger is an electronic device that records data over time or in relation to the location.
The logger are small, porteble and battery powered.
2. Data loggers are equipped with an internal memory and record data over a period of time.
Electrical recording device
http://www.onsetcomp.com/what-is-a-data-logger (1.); http://www.omega.com/prodinfo/dataloggers.html (2.)
Author: Anja Muskowitz