Blinking is the ability to teleport from one location to another, either through direct line of sight or relative sense of the location (eg. thinking of a place you have previously visited then forcing yourself to blink will teleport you to that place). Blinking is a ability possessed naturally by some beings such as Hacker but it can also be achieved by use of a blinker.
A blinker is a device that allows the user to teleport through direct line of sight. To use a blinker, the user must turn on the device's targetting scope which taps into the brain's optical nerves allowing it to see what the user sees. The user must then blink at where they wish to be teleported & retain a mental image of the location. The blinker then uses this image to lock onto it's target location & teleport the user.