The "shag" is the hairstyle of 2015.

There is only one thing you need to know about beauty trends this year, so listen up: the ’70s are in.

And when it comes to the ’70s, one hairstyle ruled supreme: the shag.

Related: 5 quick and easy hairstyles for hectic mornings (like today).  

Wait! Come back! I’m talking about all the good elements of the shag – the height and volume, the movement, the carefree glamour – without all the cringeworthy parts we don’t like.

Who rocks the shag today? Oh, I don’t know, only the coolest celebrities and models ever, such as Alexa Chung, Taylor Swift and supermodel Karlie Kloss. And need I mention that the most iconic rockstars and actresses of all time have also sported this style? I’m talking about Stevie Nicks, Patti Smith and of course, Farrah Fawcett.

Need further proof? Check out our gallery below. (Post continues after gallery.)

Also known as the “swag”, this new take on '70s classic style is all about wavy layers paired with a heavy, centre-parted fringe which stops at the tops of your cheekbones. The fringe is key, as it will frame your heavily lined and mascaraed eyes, all of which are essential for seducing – nay, becoming – a rockstar.

This century, forget about the feathery flicks. With the new shag, you want messy, healthy layers, which are scrunched to accentuate a natural (or heat-styler induced) wave. It’s a far cry from that running-along-the-beach Charlie’s Angels look.

In fact, there’s nothing beachy or sweet about this style. Stylist to the stars, Garren, told Style.com, “The shag had movement and you can put your hands through it, while beachy hair is more Victoria’s Secret and sexy - we wanted to take the sex out of it and make it cool.”

Related: How to style a short bob: 4 fast hairstyles.  

Whatever your hair situation, the new shag is the ultimate hairstyle for those of us caught between wanting a fashionable hairstyle, and being scared of the consequences.

Related: 4 at-home beauty treatments you should NEVER do yourself.

If done right, a shag haircut should be low-maintenance, requiring only a standard wash (with a hydrating shampoo like Organic Care Dry Nourish Ultra Hydrating Shampoo, $3.55) then a quick, upwards blast with a blowdryer, using your fingers to shake the layers out. New York-based hair stylist Tommy Buckett told Harper’s Bazaar, “You can just air dry or blow dry to get a little oomph in the hair and it falls in place perfectly”. A little volume powder at the roots, a spritz of hairspray through the mid-lengths and styling pomade on the ends, and you’re good to go.

And, over time, the fringe and layers of the swag are long enough to be grown out with elegance and subtlety, and by the next season, you’ll be ready to try the next hot trend.

But for the time being, make like Austin Powers, and tell people what you did to your hair, without apology: “I shagged it! I shagged it rotten, baby, yeah!”

Related: The one hair trend we didn’t see coming.