What is an electronic cigarette? It consists of an battery part, an atomizer and a cartridge which is filled with liquid. 

When you inhale an [http://www.riva-ecigar.com/ electronic cigarette], air goes though the atomizer, the battery part automatically heats the resisters of the atomizer, which vapors the liquid that is actually a kind of nicotine replacement. 

So you inhale the vapor when you smoke an electronic cigarette.