Choking: That is stopping up the carburettor air inlet. The engine can't suck in air so it sucks fuel from the fuel tank instead while you are turning the engine. You can also force the fuel to the carburettor by stopping up the exhaust outlet. This forces the exhaust air to go into the fuel tank which in turn forces the fuel into the carburettor. You have to get the fuel to the carburettor or you will flip the engine all day long without it starting.

You can spot the people at a field who never learned how to prime an engine by choking it. They are the ones who spin and spin and spin their engines for a half minute or so with their electric starters before this finally gets the fuel to the carb and the engine finally starts. If you want to start your engine without an electric starter, you will have to learn the art of priming it properly.

Throttle: Thats the thing that the throttle servo in your plane opens and closes to control the speed of the engine.

Glow Plug: Glow engines don't use spark plugs, instead they use a glow plug in the cylinder head. It has a small coil of platinum wire that glows red hot when you connect a 1.5 volt battery to it. This red hot wire is what ignites your fuel/air mixture. After the engine is running, the battery is disconnected and the plug stays red hot from the burning fuel.