Itty Bitty Buggy: Car Movement Tutorial (mDesigner)
From Microduino Wiki
Car
Car blocks are blocks which controls both of the Motors at the same time in order to move the forward / backwards (Car - Move block) or turn left / right (Car - Turn block). These are convenience functions designed to be "general purpose". Motors can be controlled directly with the Motor blocks. See section #Motors.
Motors
Motor blocks are blocks which controls the Motors on Buggy Base directly. This gives the user the ability to fine tune the behavior of the Motors. These blocks can set the movement direction of the motors (Motor - Set Speed block) or brake / stop the motors (Motor - Brake block).