Bits per second, abbreviated bps, describes an information rate: how many binary units of information a system transmits in one second. A higher number means more information can move during that time, but the value is useful only when the method of measurement is clear.
In brain-computer interface research, an information rate may summarize how rapidly a person can make selections or send commands. A separate raw data rate may describe signals moving from implanted electrodes to a processor. These are not interchangeable: collecting a large amount of neural data does not mean a person can communicate at the same rate.
Accuracy, selection choices, error correction, trial setup and time spent recalibrating all affect a meaningful communication-rate calculation. Researchers may also report words per minute, characters per minute or completed tasks, which can be easier to understand but cannot always be converted directly into a fair bps comparison.
When comparing BCI speed claims, look for the formula used, whether errors and pauses are included, and whether the number comes from laboratory sessions or independent everyday use. The highest reported instantaneous rate is not necessarily the most useful real-world performance.