Back story: Intel has been developing a new technology to replace USB, which is how most peripherals connect to PCs. This new tech, originally called LightPeak, was supposed to use optical cables instead of copper wire to connect to the PC because optical cable is generally faster than copper. Well, the first version of LightPeak is actually going to have copper wire anyway. And the first version is debuting exclusively on Apple computers. And it’s being called Thunderbolt.
Ziller also addressed the optical connection question. Though originally code-named Light Peak–which makes an obvious reference to optical technology–the connector is currently being implemented as an electrical technology based on copper.