recorder is a device that records data about the operation of train controls and performance in response to those controls and other train control systems. An accident data recorder (ADR) is a device for triggering accidents or incidents in most kind of land vehicles and recording the relevant data. In automobiles, all diagnostic trouble codes (DTCs) are logged in engine control units (ECUs) so that at the time of service of a vehicle, a service engineer will read all the DTCs using Tech-2 or similar tools connected to the on-board diagnostics port, and will come to know problems occurred in the vehicle. Sometimes a small OBD data logger is plugged into the same port to continuously record vehicle data. In embedded system and digital electronics design, specialized high-speed digital data logger help overcome the limitations of more traditional instruments such as the oscilloscope and the logic analyzer. The main advantage of a data logger is its ability to record very long traces, which proves very useful when trying to correct functional bugs that happen once in while. In the racing industry, Data Loggers are used to record data such as braking points, lap/sector timing, and track maps, as well as any on-board vehicle sensors. Health data loggers: The growing, preparation, storage and transportation of food. Data logger is generally used for data storage and these are small in size. A Holter monitor is a portable device for continuously monitoring various electrical activity of the cardiovascular system for at least 24 hours. Electronic health record loggers. Other general data acquisition loggers: An (scientific) experimental testing data acquisition tool. Ultra Wideband Data Recorder, high-speed data recording up to 2 Giga Samples per second. Future directions Data Loggers are changing more rapidly now than ever before. The original model of a stand-alone data logger is changed to one of a device that collects data but also has access to wireless communications for alarming of events, automatic reporting of data, and remote control. Data loggers are beginning to serve web pages for current readings, e-mail their alarms, and FTP their daily results into databases or direct to the users. Very recently, there is a trend to move away from proprietary products with commercial software to open-source software and hardware devices. The Raspberry Pi single-board computer is among others a popular platform hosting real-time Linux or preemptive-kernel Linux operating systems with many digital interfaces like