There are dozens of different kinds of ocular implants and they are used for a variety of purposes. Some ocular implants are as simple as contacts with a heads-up display. Others require surgery, and are more permanent. Ocular implants are frequently used by combat soldiers for identifying targets, range, distance, threat level, etc. They can even detect body heat and motion. They have been used by pilots, miners, hunters, inspectors, and a host of other professions.