State-of-the-art implant technologies include inserting signals into the brain and extracting signals from it. Implants are used to connect with the peripheral nervous system with electrical signals and microchips in silicon capsules can store data, sensors and positioning devices. The most common applications to-date are medical, i.e., to manage Parkinson's disease, correct deafness and help people who have lost limbs or suffer from severe motor disabilities. However, implants raise questions about body modification for enhancment rather than therapeutic purposes, and if they should be used for identification or tracking.