The next big hair trend is one that would make your Year 10 self cheer.

Kristen Stewart with straightened hair (Image: Getty.)

Heat up your hair straighteners, and arm yourselves with styling serums and protective sprays, because straightened hair is back.

That’s right, the hair trend you obsessed over in Year 10 has finally returned. And thank goodness for that, because boy are my arms tired from braiding, rag-curling and heat styling my naturally straight hair into waves.

The “new straight” is less about looking like Jennifer Aniston circa season 6 of Friends, and more about using the straight, supple hair as a base for sleek, modern hairstyles.

A sophisticated way to wear straightened hair is by creating an unusual parting. Margot Robbie (below) at the Oscars earlier this year is a stunning example, with her dramatic side part. Don’t pretend you didn’t try out this hairstyle in the bathroom, straight after you saw it. Kristen Stewart (top) also shows us how it’s done, by rocking her straightened, shorter hair flipped back off her face.

So, why the current fascination with straightened locks? Well, it may all come down to hair health.

"The reason why women are embracing uber-straight hair again is because sleek, straight hair equals shiny hair," says Barney Martin, Pantene Hair Expert and owner of Barney Martin Hair Salon.

If you're already blessed with straight hair, then achieving this streamlined style should be a breeze, as long as you have the right styling products and tools at hand.

"Apply a leave-in treatment, such as Pantene Ultimate 10 BB Crème For Hair, $10.99, and blow-dry the hair sleek with a large round bristle brush (we like the Lady Jayne Boar Bristle Paddle Brush, $23.99) then use a straightening iron and a serum to get the hair extra smooth and sleek," recommends Martin.

For those curly girls - of whom I am so envious - Martin recommends blow-drying the hair straight, and then going over it again with a flat heat styler. But, where possible, try to get as much of the straightening done with your trusty blow-dryer.

"Try to get the hair blow-dried as straight as possible, as over-use of flat irons can damage the hair," suggests Martin.

Before using a heat styler, Martin emphasises that a heat protectant spray is essential. Once that's done, begin straightening your hair slowly and steadily.

"Taking small sections of hair at a time, begin at the roots and run the straightener through slowly, towards the ends of your hair. To finish off the look, apply a hair oil to smooth down fly-aways and add shine to the hair," suggests Martin. (Post continues after gallery.)

But in case you're still confused about the difference between "noughties straight" and "now straight", here's some handy visuals.

Now: Behati Prinsloo at an art exhibition.

Victoria's Secret model, Behati Prinsloo wears her straightened hair with a hint of texture and fringe. The mid-length volume can be achieved with some subtle teasing and scrunching. This messy take on the straight hair trend strikes the perfect rock chick vibe.

Then: Jennifer Aniston in any of the later seasons of "Friends".

It's too straight and smooth to look modern. Wearing limp, flat hair hanging in your face can look very dated. Sorry, Rachel.

Now: Mindy Kaling at the Emmys, 2015.

It's straight yet with a bouffant, and the sides are swept back. Instant glamour. Go Mindy!

Then: Any of the girls from S Club 7.

Definitely avoid anything that's straight and boring. Actually, just don't take any style cues from this image in general, for your own safety.

Did you straighten your hair to death in the noughties? Are you excited that straightened hair is back?