The seventies are back for this year's fall trends. From flared pants to platform shoes, you can't really escape a store without seeing something that reminds you of Donna's clothing in That 70s Show. But if you can recall, in past years nineties grunge and sixties hippie styles were all the rage. Thrift shopping and vintage clothing stores are also very popular among young people. So why are we so obsessed with the past?

Nostalgia can be defined as "A sentimental longing or wistful affection for the past, typically for a period or place with happy personal associations." But half of the people wearing these seventies clothes right now weren't even born before 2000.

These trends are so appealing to young people because we have access to all of the movies, TV shows, and music from the past. We have the whole world's history to our disposal.

Yes, I may not have been a teenager in the nineties, but thanks to watching too many episodes of "Freaks and Geeks", I can feel like I was. When you fall in love with a certain show or movie or band, you tend to want to mold your life, and your style, around it.

Big fashion companies sense our longing and play into it. I didn't even know I liked the 90s grunge style so much until I started seeing it everywhere. It was different, it was cool, and it reminded me of Tai from "Clueless" (pre-makeover of course).

We also tend to love the past if our current state of being isn't satisfying. Today I overheard someone say "Wow look at everyone on their phones. We're exactly what older people think of when they think of millennials. I wish I was born in like, 1925, or something." Obviously, he didn't mean that, but it is nice to think of a time where people had to go out of their way to get in contact with one another.

We love looking back on the "good old days" with rose-colored glasses and romanticizing the idea of a technology-free world, and so companies take advantage of our longing and we love every second of pretending to be someone we're not.

Fashion echoes our longings. Jeans sprang up because people needed better, more durable pants to work in. Skirts became shorter when women decided they were tired of being restricted. And now, clothing of the past is becoming more prominent because we miss the simplicity of a time we never got to experience in the first place.

It's really interesting to think about how maybe ten or twenty years from now, our kids will want to be wearing some of the trends that have arisen on their own in our generation like "insta-thot" clothing and, of course, athleisure. Maybe they'll even like the clothes we look back on in disgust (so basically every outfit I wore in middle school).