The first thing that you want to know before buying an electric aroma diffuser is what's the difference between a diffuser and a humidifier? The answer is your choice will depend on the type of room, but in general, they can be used to help make your living space smell better. Around the world, I haven't seen a single room without one of these devices. They are basically a device that diffuses warm air into the air, thereby giving a more vibrant, healthy-looking environment. They are also recommended as an excellent device for people suffering from allergies and asthma.