Brain-computer interface (BCI) is a fast-growing emergent technology, in which researchers aim to build a direct channel between the human brain and the computer. A Brain Computer Interface (BCI) is a collaboration in which a brain accepts and controls a mechanical device as a natural part of its representation of the body. Computer-brain interfaces are designed to restore sensory function, transmit sensory information to the brain, or stimulate the brain through artificially generated electrical signals.The main motivation for the BCI was In USA, more than 200,000 patients live with the motor  sequelae (consequences) of serious injury. There are two ways to help them restore some motor function: Repair the damaged nerve axons. Build neuroprosthetic device. The main applications of BCI are Artificial Sensory channel ,Artificial Hearing ,Artificial Vision,Artificial Motor Channel . Neural Disorder Control Parkinson’s disease Seizure prediction and control .The field of BCI research and development has since focused primarily onneuroprosthetics applications that aim at restoring damagedhearingsight and movement.The main advantage of  BCI are BCIs will help creating a Direct communication pathway between a human or animal brain and any external devices like computers.

BCI has increased the possibility of treatment of disabilities related to nervous system along with the old technique of Neuroprosthetics .Techniques like EEG,MEG and neurochips have come into discussions since the BCI application have started developing. This has provided a new work area for scientists and researchersaround the world. The main disadvantages of BCI are In case of Invasive BCI there is a risk of formation of scar tissue like EEG BCI techniques still require much enhancement .

At present BCI will works wirelessly. A few paralyzed patients could soon be using a wireless brain-computer interface able to stream their thought commands as quickly as a home internet connection.The device was developed by a consortium, called BrainGate, which is based at Brown and was among the first to place implants in the brains of paralyzed people and show that electrical signals emitted by neurons inside the cortex could be recorded, then used to steer a wheelchair or direct a robotic arm.

Indicators and predictions of the future BCI are By 2018, most of us will be controlling our computers or gaming devices with some form of naturalinput such as speech, touch,sight, brain waves, etc. Thisfirst wave of natural input devices will include brain signalscontrol, a major first step towards social awareness of BCIand encourages development in BCI.The advancement of nanotechnology will mayhelp us to create smaller and far superior chips. In around2020 to 2025, we will start seeing the first batch of researchers using computers to simulate human brains. If quantum computing arrives, we may see this happening even faster.