Heart Rate Altitude Temperature black Bicycle Computers
Heart Rate Monitoring allows a sensor, often a chest strap, to transmit your heart rate to your computer. Heart rates monitors are typically wireless.
Some computers come with built-in altimeters, which will display the current altitude. GPS enabled computers can often do this more accurately.
Temperature monitoring allows for a computer to tell you the current temperature.
Heart Rate Monitoring allows a sensor, often a chest strap, to transmit your heart rate to your computer. Heart rates monitors are typically wireless.
GPS, or Global Positioning System, is a satellite based system that provides accurate location and altitude information.
Some cycling computers can display a power reading, usually in watts. They usually require a separate sensor - in some cases a special hub or crank arm. A few will estimate the value based on speed, cadence, rider weight or other data. "Optional" means it can read from a separate power meter or sensor. "Included" means it is calculated by the computer or includes the neccessary sensor.