1. The range of frequencies over which a given device is designed to operate within specified limits. 2. The differences between half-power points, i.e., the frequencies at which the power drops to half the peak power (3 dB). 3. The effective bandwidth is
where p(f) is the power at the frequency f and pmax is the maximum power. It is the width of a boxcar with the same total power and the same peak power. 4. The rate at which a computer resource can carry (accept or deliver) data. Usually expressed in bytes per second or bits per second.