Ah keratin, most confusing and seductive of straightening treatments. There's a lot of marketing, a lot of conflicting information, and a lot of people with follicular/emotional scarring from the Great Brazilian Freakout of '09 (NEVER FORGET). Usually, we'd just run around screaming “Keratiiiiiin' like ersatz beauty-industry versions of Animal from The Muppets, but this is important, so instead we teamed up with Rudy Pena, the “Curl and DeFrizz Specialist' (great job title) at Julien Farel Salon—he does this all day, every day—for a handy straightening guide.

Here are 10 key facts about keratin (plus a Beyoncé hair gif, because welcome to the internet):

Fact the First: WTF Is Keratin Straightening? This TF Is Keratin Straightening

Your hair is made of keratin, so a keratin treatment pretty much consists of marinating yourself in even more of the stuff until it sticks (heat helps this process). It smooths out the surface of follicles and, depending on how much you use, releases curls, takes out waves, etc. It makes hair shinier and helps prevent breakage, too. It's not cheap—salons can charge anywhere from $200–$600—and it's tricky. So don't grab the first Groupon you see.

Fact 2: Keratin Treatments, Unlike Face Tattoos, Aren't Permanent

Keratin washes out eventually. Most treatments last about eight weeks, but it could be up to six months. Obviously, this is something you want to ask about beforehand unless you enjoy literally any kind of surprise, even like “Surprise! Your hair is straight for half a year!”

Fact 3: Keratin Straighteners Shouldn't Be Carcinogenic

If you're freaked out by the low level of formaldehyde that's produced during classic keratin treatments, be direct when you make your appointment and say you'll only accept formaldehyde-free services (there are a lot of new options). “Not only is it a more pleasant olfactory experience, it's also safer for your skin and eyes!” Pena says.

Fact 4: You Can Use Keratin To Get Rid Of Frizz Without Straightening Your Curls

If all you want is slightly smoother texture, keratin can do that, too. Ask for a weaker formulation that won't release curls. Pena loves the Zero Frizz Quickie treatment in particular because “there's no downtime; you can wash your hair that night, and you're back to natural in six to eight weeks!” Coincidentally, Pena also created Zero Frizz Quickie, but we won't hold that against him.

Fact 5: There Are Tons Of Different Keratin Treatments For Different Hair Types

It's not one-size-fits-all. In fact, you don't want a salon that only offers a single keratin treatment, because it's probably not the best one for your texture and thickness. “If you use the same formula on fine hair that you do on thick, it'll just be flat and stick to your scalp!” Pena explains. And on the flip side, if the formula's not strong enough, it'll be like you just spent $400 on...absolutely nothing.

Fact 6: Keratin Works On Straight Hair, Too

Got coarse, thick, frizzy hair that's straight? Keratin could be your new favorite thing. A light treatment can make it shinier and smoother, so you only have bed head if you actually want it.

Fact 7: Keratin Straighteners Aren't Relaxers

Unlike keratin, relaxers are permanent. They change your texture, so you have to want stick-straight hair forever—or at least until your roots need touching up. They're also easier to do at home, whereas keratin treatments are usually in salons.

Fact 8: Keratin Straightening Isn't (Or At Least Shouldn't Be) A Super-Intensive Process

A stylist combs a bunch of it into your strands, leaves it on 'til your follicles are good and coated, then flat irons your hair to seal it in. Older formulas require you not to wash or style your hair for 72 hours, which is why you should find a place that uses newer no-wait straighteners if you can.

Fact 9: You Can, In Fact, Use Keratin Treatments On Dyed Or Bleached Hair

They can actually make bleached hair feel healthier. The same doesn't hold true for other straighteners, though. “If your hair's dyed, stay away from flat irons, relaxers, or Japanese straightening!” Pena warns.

Fact 10: Maintenance Is The Key To Keratin Success

If you want your fancy new shininess to last, you might have to drop your regular shampoo and stop washing so much altogether. You can shampoo three times a week max, but there better not be actual suds involved. “Stay away from cleansers that bubble!” Pena advises. “If your shampoo has a detergent ingredient like Sodium Laureth Sulfate (SLS), which is literally found in laundry soap, it'll just strip your hair!” (Good sulfate-free lines: Pureology Essential Repair and Living Proof No Frizz Shampoo and Conditioner.) Also no good? Salt water and chlorine. So surf spray's not an option, and make sure to coat your hair with a protective cream or oil before you make any literal waves.

If you have more questions, let us know about your keratin concerns in the comments and we'll try to get them answered by Mr. Pena himself!

Photographed by Emily Weiss.