This is a very small light sensor. A photo resistor (also known as a photodector, or photocell) changes resistance depending on the amount of light it is exposed to.
This is a SDR 4-wheel drive remote control robot kit. It uses four powerful wheelchair motors and 35AH batteries.
The Micro Maestro is the smallest of Pololu’s second-generation USB servo controllers. The Maestros are available in four sizes and can be purchased fully assembled or as partial kits.