In 1929, Hans Berger made an important discovery for neurology and all other sciences that study the brain and its functions. This discovery became known as the electroencephalogram (EEG). Thanks to Hans Berger's discovery, brain-computer interface (BCI) methods were developed years later. The BCI is a human-machine interface, which means that a person can operate a machine without using their peripheral nervous system. Since you don't have to move to control a machine using a BCI, this opens up a whole new range of possibilities that is particularly interesting for people who, for example, have suffered a stroke and are therefore unable to move. This gives these people a new way of communicating and moving around.