1) Brain-computer interface is a direct communication pathway between the brain and an external device that reads brain activity without muscle movements and translates it into commands for computers and other devices. 2) The objective of BCI is to develop a fast and reliable connection between the brain of a severely disabled person and a personal computer to allow communication and control through thought alone. 3) BCI research has progressed from animal experiments to human trials, allowing paralyzed patients to control devices and communicate just by thinking. However, widespread adoption is still limited by challenges with sensor accuracy, information transfer rates, and system costs.