A monitoring apparatus that includes a sensor device and an I/O device in
communication with the sensor device that generates derived data using
the data from the sensor device. The derived data cannot be directly
detected by the associated sensors. Alternatively, an apparatus that
includes a wearable sensor device and an I/O device in communication with
the sensor device that includes means for displaying information and a
dial for entering information. Alternatively, an apparatus for tracking
caloric consumption and caloric expenditure data that includes a sensor
device and an I/O device in communication with the sensor device. The
sensor device includes a processor programmed to generate data relating
to caloric expenditure from sensor data. Alternatively, an apparatus for
tracking caloric information for an individual that utilizes a plurality
of classification identifiers for classifying meals consumed by the
individual, each of the classification identifiers having a corresponding
caloric amount.