Bit per second, Bandwidth
The bit rate is quantified using the 'bit per second' (bit/s or bps) unit, often in conjunction with a SI prefix such as kilo (kbit/s or kbps), Mega (Mbit/s or Mbps), Giga (Gbit/s or Gbps) or Tera (Tbit/s or Tbps). Read more 
When used to discuss digital communication, the meaning of "bandwidth" is clouded by metaphorical use. Technicians sometimes use it as slang for baud rate, the rate at which symbols may be transmitted through the system. It is also used more colloquially to describe channel capacity, the rate at which bits may be transmitted through the system.
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