Switch
The switch on most vacuum cleaners is usually hidden deep under the moulded plastic body. The range of mains powered switches is pretty vast from various types of rocker switch which include illumination or symbols to indicate their state, to push buttons.
Again, when selecting a switch the most important factor is safety, you want to ensure it is rated for the amount of power being draw, I choose a 13 amp, 230 volt switch. You could also exclude a switch in many countries and just control it through the mains outlet, however it is less convenient and not all countries have a switched outlet as standard.