The basics of any engine is that it is an air pump and requires fuel,air and heat (Glow plug) to run. Other factor effect the performance, such as compression and timing. With a 2 stroke engine the engine fires once every rotation of the crank shaft. Anyway the glow plug works much like the catalitic converter in your car. When sufficiently heated it will stay hot to burn the Hydrocarbons present (Fuel). If you look down the open throat of the carburetor while rotating the crank shaft you will see that the crank shaft has an opening in it and that from that opening to the back of the crank shaft is hollow. As the piston is comming down and that opening is facing up (to the carburetor) the suction (vacume) produced by the pistons movement draws air and fuel into the crank case and into the cylinder. Thus providing fuel and lubrication to the engine. As the piston comes back up it compresses the fuel air mixture in the cylinder and the glow plug ignites the mixture forcing the piston downward again to repeat the cycle. As the piston is going down the exhaust port (ports are openings machined into the cylinder wall) is the first to be exposed allowing the burnt fuel to escape. Then the intake ports are cleared and more fuel/air mixture is drawn into the cylinder accelerated by the rush of exhaust gasses escaping in the opposite direction.

I'm sure there are more technical explainations but this is my understanding of the two stroke engine.

Others; feel free to elaborate or correct as you see fit.