250x250px|The Fitbit Alta HR, a wearable device capable of tracking a person's sleep. Sleep tracking is the process of tracking a person's sleep, which is done most commonly through measuring inactivity and movement to estimate sleep. A device that tracks a person's sleep is called a sleep tracker.  Sleep trackers are capable of tracking the stages of a person's sleep (light sleep, deep sleep, REM sleep), the length/duration of a person's sleep, the quality of a person's sleep, and the consistency of a person's sleep. Some sleep trackers offer other features, such as "sleep scores" that rank how well a person slept, "smart alarms" that wake a person up within a set period of time based on the circumstances of the person's sleep, and the ability to track the amount of light and/or the temperature in the person's bedroom . Devices capable of tracking a person's sleep include dedicated sleep trackers, trackers that clip onto a person's pillow, smartphones, fitness trackers, smartwatches, and other wearable devices .
250x250px|The Fitbit Alta HR, a wearable device capable of tracking a person's sleep. Sleep tracking is the process of monitoring a person's sleep, which is done most commonly through measuring inactivity and movement to estimate sleep. A device that tracks a person's sleep is called a sleep tracker. Devices capable of tracking a person's sleep include dedicated sleep trackers, trackers that clip onto a person's pillow, smartphones, fitness trackers, smartwatches, and other wearable devices. Sleep trackers are capable of tracking the stages of a person's sleep (light sleep, deep sleep, REM sleep), the length/duration of a person's sleep, the quality of a person's sleep, and the consistency of a person's sleep. Some sleep trackers offer other features, such as "sleep scores" that rank how well a person slept, "smart alarms" that wake a person up within a set period of time based on the circumstances of the person's sleep, and the ability to track the amount of light and/or the temperature in the person's bedroom .
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Devices capable of tracking a person's sleep include dedicated sleep trackers, trackers that clip onto a person's pillow, smartphones, fitness trackers, smartwatches, and other wearable devices.
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. Devices capable of tracking a person's sleep include dedicated sleep trackers, trackers that clip onto a person's pillow, smartphones, fitness trackers, smartwatches, and other wearable devices