Telematics is full of acronyms. This glossary defines 26 of the most common fleet management and GPS-tracking terms in plain English — accurate, vendor-neutral, and free to reference.
26 terms
A GPS device used to locate non-powered or intermittently powered equipment such as trailers, containers, generators, and tools. Because many assets have no continuous power source, asset trackers typically run on long-life batteries and report position on a schedule — for example once or twice a day — rather than continuously. This conserves battery while still giving you a recent known location for recovery, utilization, and theft deterrence.
The connected series of timestamped GPS points a vehicle records as it moves, which together reconstruct the exact path it traveled. Each "breadcrumb" captures position and usually speed and heading, so dispatchers can replay a trip second by second. Breadcrumb trails are the basis for trip history, route verification, and resolving delivery or timesheet disputes.
The internal communication network that lets a vehicle’s electronic control units exchange data without a central host computer. Engine, transmission, braking, and body modules broadcast messages on the CAN bus, and a telematics device can read these to capture fuel level, RPM, odometer, and fault data. It is the backbone of modern in-vehicle data and the channel most telematics hardware taps into.
A technique for estimating a vehicle’s position when a GPS signal is lost — for example in tunnels, parking structures, or dense urban canyons. The device calculates location from the last known fix combined with motion sensors such as speed, heading, and accelerometer or gyroscope data. Dead reckoning keeps the breadcrumb trail continuous until satellite positioning is reacquired.
The function of assigning drivers and vehicles to jobs, routes, or service calls and coordinating them in real time. Modern dispatch software combines live vehicle locations, job status, and two-way driver messaging so coordinators can pick the right unit and reroute on the fly. Effective dispatch shortens response times and reduces empty miles.
A summary that rates an individual driver’s safety and efficiency based on telematics events such as harsh braking, rapid acceleration, sharp cornering, speeding, and idling. Each behavior is weighted and combined into a score that lets fleets benchmark drivers, target coaching, and recognize safe performers. Used consistently, scorecards are associated with lower incident rates and insurance costs.
A standardized code a vehicle generates when an onboard system detects a fault, often accompanied by a dashboard warning light. Codes follow the OBD-II format — a letter for the subsystem (P for powertrain, B for body, C for chassis, U for network) followed by digits identifying the specific fault. Surfacing DTCs through telematics lets fleets diagnose issues remotely and schedule repairs before a breakdown.
A record of the pre-trip and post-trip safety inspection a driver performs on a commercial vehicle, documenting the condition of brakes, tires, lights, and other components. In the United States, the FMCSA requires DVIRs for many commercial vehicles, and defects must be repaired or certified safe before the vehicle returns to service. Electronic DVIR apps replace paper forms and route defects straight to maintenance.
The amount of time a vehicle remains stopped at a particular location, such as a customer site, depot, or loading dock. It is measured from arrival to departure and is often calculated automatically when a vehicle enters and exits a geofence. Tracking dwell time helps fleets bill accurately, spot bottlenecks at facilities, and improve scheduling.
A device that automatically records a commercial driver’s hours of service by connecting to the vehicle’s engine to capture driving time, engine hours, location, and movement. In the United States the FMCSA ELD mandate requires most drivers who must keep records of duty status to use a registered, compliant device. ELDs replace paper logbooks and reduce errors and HOS violations.
A virtual boundary drawn on a map around a real-world location such as a job site, depot, customer, or restricted zone. When a tracked vehicle or asset enters or exits the boundary, the system can log the event and trigger alerts, automatic arrival and departure timestamps, or reports. Geofences power features like dwell-time tracking, unauthorized-use alerts, and proof of site visits.
An approach to telematics in which the platform exposes documented APIs and a marketplace of add-ins so third parties can extend it and integrate other software. Open platforms let fleets connect telematics to fuel cards, maintenance systems, ERPs, and custom dashboards rather than being locked into one vendor’s tools. The trade-off is greater flexibility in exchange for more configuration.
The use of satellite positioning to determine and record a vehicle’s location over time and display it on a map. A tracking device receives signals from positioning satellites, calculates its coordinates, and transmits them over a cellular network to a fleet platform. GPS tracking underpins live maps, route history, geofencing, and most other telematics features.
A sudden vehicle motion — hard braking, rapid acceleration, sharp cornering, or an impact — detected when an accelerometer reading crosses a defined threshold. These events are leading indicators of risky driving and can also flag potential collisions. Fleets feed harsh-event data into driver scorecards and safety coaching, and may pair it with camera footage for context.
The regulations that limit how long commercial drivers may drive and work before they must rest, designed to reduce fatigue-related crashes. In the United States the FMCSA sets daily and weekly driving and on-duty limits and mandatory break and rest periods. ELDs track driving time automatically and warn drivers and managers as they approach a limit.
The period a vehicle’s engine runs while the vehicle is stationary — for example waiting, loading, or warming up. Excessive idling wastes fuel, adds engine wear and emissions, and can signal inefficient routing or driver habits. Fleets monitor idle time to cut fuel costs and may set alerts when idling exceeds a chosen threshold.
An agreement among the U.S. states and Canadian provinces that simplifies fuel-tax reporting for motor carriers operating across jurisdictions. Instead of filing in every state entered, a carrier files one quarterly return that distributes fuel taxes based on miles driven in each jurisdiction. Telematics simplifies IFTA by automatically logging distance traveled per state, removing manual mileage tallies.
GNSS (Global Navigation Satellite System) is the umbrella term for satellite positioning networks, of which the U.S. GPS is one. A multi-constellation receiver uses several systems at once — such as GPS, GLONASS, Galileo, and BeiDou — to lock onto more satellites simultaneously. The result is faster fixes and better accuracy, especially in cities and other areas where the sky is partly obstructed.
A standardized diagnostic system and physical port found in virtually all light-duty vehicles sold in the United States since 1996. The OBD-II port exposes engine and emissions data and diagnostic trouble codes, and a plug-in telematics device can read it without professional installation. It is the most common way to add tracking and engine data to cars and light trucks.
A maintenance strategy that uses vehicle data — engine hours, mileage, fault codes, and sensor trends — to service components before they fail rather than on a fixed calendar. By acting on early warning signs, fleets reduce unplanned breakdowns and roadside failures and extend asset life. It contrasts with reactive (run-to-failure) and purely time-based preventive maintenance.
Documentation confirming that goods or services reached the correct destination, traditionally a signed paper receipt. Digital POD captures a signature, photos, timestamp, and GPS location at the point of completion and attaches them to the job record. Combined with geofence arrival data and breadcrumb trails, it settles disputes and speeds up billing.
A mechanism that diverts engine power to operate auxiliary equipment such as a dump-bed lift, crane, mixer, or hydraulic pump. Because PTO work happens while the vehicle is parked, telematics can monitor a PTO input to distinguish productive on-site engine use from wasteful idling. This gives a truer picture of utilization for work trucks.
A refrigerated trailer or truck body with its own cooling unit, used to haul temperature-sensitive freight such as food, beverages, and pharmaceuticals. Reefer monitoring adds temperature and door sensors so a fleet can verify the cold chain was maintained end to end. Temperature alerts help prevent spoilage and provide an auditable record for compliance.
The combination of telecommunications and informatics — the technology that gathers data from a vehicle and transmits it to a remote platform for monitoring and analysis. A telematics device captures GPS position along with engine and sensor data, then sends it over a cellular network to fleet software. It is the foundation for tracking, diagnostics, driver behavior, and compliance features.
A discrete journey segmented automatically from a vehicle’s continuous data stream, typically bounded by an ignition-on start and an ignition-off end. Each trip records start and end times and locations, distance, duration, and the breadcrumb path between them. Trips are the unit fleets use for mileage logs, utilization reporting, and reconstructing a day’s activity.
A measure of how productively a vehicle or asset is used over a period — for example active hours, miles driven, or days in service versus days available. Low utilization can reveal underused or redundant assets that a fleet could rightsize, reassign, or sell. Tracking utilization helps balance a fleet to actual demand and control ownership costs.
From geofencing to driver scorecards, TrackPro puts the whole glossary to work on one platform. Get a walkthrough tailored to your fleet size and industry.