Both vaporizers and electronic cigarettes provide a much healthier alternative to smoking of any kind. The reason is that only the active ingridient of the material inhaled. You leave all the toxic chemicals, tar, carbon monoxide and other harmful stuff out of your body. We see an increased percentage of demand for these devices and more vaporizers are encouraged to be used with prescription medicine nowadays.

The common difference between a vaporizer and e-cigarette seems to be the usage areas. E-cigarettes tend to be used more for social environments and used for quitting smoking traditional tobacco cigarettes where vaporizers are used more in aromatherapy. Electronic cigarettes are often found in disposable or short term usage form while vaporizers are intended for longer term usage. E-cigarettes also use mostly liquid form of ingridents towards atomizers or cartridges while vaporizer tend to use all forms such as liquid, wax, dry herb and oils. The size of the vaporizers vary greatly while the size of an e-cigarette is often limited. 

Vaporizers in general are more sophisticated devices than e-cigarettes. You can find precision in temperature control, material management, accessories offered etc. There is also a wide range of prices for vaporizers while the e-cigarette prices are usually on the low end of the price spectrum.

Common material for an e-cigarette is nicotine while vaporizers can be used with many different plant herbs, oils and medicine in wax, oil, liquid form.

In summary, both type of devices use the same technique for operation and they both provide a health way of inhaling subsctance. The difference is the purpose of usage. Hope you will find this helpful while you are making a decision of buying a vaporizer vs an e-cigarette.