Almost 30 years ago we watched Marty McFly — played by Michael J. Fox — fly into the future, to Oct. 21, 2015.

To commemorate the anniversary of "Back to the Future," we've come up with nine lessons we learned from the trilogy.

Note: Amazon Prime subscribers can stream all three Back to the Future movies to celebrate.

Nothing is impossible

Growing up, many readers eagerly anticipated a new and innovative world that would exist in 2015.

While some of the film's imagined inventions have actualized (Nike announced the release of self-lacing shoes, according to International Business Times), others have yet to be fully realized (cue the oft-heard laments of the lack of hoverboards or a flying car interstate).

The fact that some of us are all still hoping for these inventions to materialize shows our collective belief in the power of imagination combined with science, and the limitless future ahead of us.

Your fate can always change

Marty and Doc spend a lot of time trying to change events from the past and the future but (spoiler alert) ultimately discover that the future is unwritten. We have control over our densities (watch the first "Back to the Future" if you didn't understand that reference.)

Watching 'Back to the Future' is infinitely more awkward as an adult

Remember that weird scene in the first "Back to the Future" when a young-Marty's mom, Lorraine, kisses him, not knowing he's actually her son? It was a weird and goofy scene to watch as a kid. It is much more uncomfortable to watch as an adult.

What a 'gigawatt' is

In short, a gigawatt is a unit of power. According to Doc, it takes 1.21 gigawatts to power a time machine. Check on Wired's take on how you can generate 1.21 gigawatts to power your time machine.

The power of recycling

In the second film, the new-and-improved DeLorean uses nuclear fusion to power the vehicle off of recycled garbage, instead of plutonium, according to the "Back to the Future" wiki page.

Don't limit yourself

The original "Back to the Future" has characters in 1955 scoffing at fictional character Goldie Wilson's aspirations to become mayor (when he was, in fact, the mayor of fictional town Hill Valley), and at the actor Ronald Reagan's chances of becoming president. Marty McFly, and we as viewers, knew differently.

A good movie — and its music — are timeless

Marty McFly became an instant hit, bringing music back from the '80s to 1955, showing us that good music transcends generations. Similar to this, the hit Huey Lewis and the News' songs "Back in Time" and "Power of Love," created for the first film, definitely have staying power.

In a nod to the staying power of a good movie, we are talking about "Back to the Future" 30 years after the first of the trilogy was created.

Change your expectations

A lot of times life doesn't turn out the way we would expect. The Cubs don't win the World Series. (They currently trail 3-0 in the National League Championship Series.) The Biffs in our lives may not be thwarted by our son going back in time and putting him in his place. We can't use garbage to power our vehicles quite yet. In some senses, we could be disappointed that things didn't turn out quite the way we wanted.

The good news? Innovation is on the rise. We have 3-D touch phones and the ability to video chat instantly with almost anyone across the globe. Life may turn out differently than we expect, but with the right perspective, it often turns out better.

BONUS: If an actor doesn't return for the second film, don't attempt to recreate his likeness

Actor Crispin Glover, who played George McFly, declined to appear in the second film. He later sued filmmakers, contending that they did not have his permission to use his likeness in the film, according to Internet Movie Database. The case was settled and the Screen Actors Guild made changes to its rules about the use of actors.