Chip key simply means there is a chip buried in the key handle. And each key chip has its unique code. To program the key actually is to make the immobilizer ecu to accept the code. Otherwise although the car is cranked, but the ecu doesn't allow the circuit for the fuel supply to work, so the engine may crank but will not start.
Unlike to program a keyless entry remote, to program the chip key, you really need the dealer's computer supplied by Toyota and installed with Toyota's specific programs and tools to do it.
I apologize if you feel I'v made rude comment on "expensive".
