There are three major types of hair dryers: ionic, ceramic and tourmaline. Ionic dryers use negative ions to shrink water droplets in the hair. Manufacturers claim this dries wet hair faster with less heat damage. Ceramic dryers contain ceramic coils. Unlike metal, this material is said to self-regulate to prevent overheating. Lastly, tourmaline, a gemstone typically added to the heater of hair dryers, is thought to generate a higher number of negative ions than regular ionic dryers. There's pretty iffy science behind all of these technologies, but in tests, the top-rated dryers all use one of these three types.
Travel hair dryers also can be smart buys, because hotels do not always have dryers. Important product features for hair dryers include airflow, heat and noise level.
It's hard not to notice the enormous price difference -- often $100 or more -- between hair dryers you'll see in drugstores and big-box stores versus those you'll see in beauty-supply stores or salons. The difference isn't just price; hair dryers made for the salon trade are made to withstand a whole day of on-and-off use. Furthermore, their product life can be 1,000 hours or more. Inexpensive home dryers, on the other hand, are made for once-a-day use and can be expected to last less than 500 hours overall.
So why pay more for a salon model? On review sites, those who seem happiest with professional dryers are those who have thick and/or wavy hair -- the kind of hair that takes a longer time to blow dry. And there's evidence in user reviews that professional dryers aren't as noisy as smaller home models.
But while product life and noise may be better overall, it's hard to ignore the price difference. In many cases, you could buy four or five less expensive home dryers before spending as much as you would on one professional model. In the end, it's up to you.