Nostalgia is a powerful substance. And everyone carries it within themselves. It can take us to a distant time and place in a heartbeat. All we need is the right trigger. Luckily, the subreddit of the same name has plenty of them.

Whether we're talking about multicolored pens, Tamagotchis, or having to manually turn off your computer, this online community shares pictures that make you feel old and hit right in the feels.

We at Bored Panda have already covered r/Nostalgia in our older publications here and here, but with 1 million members, its collection of sentimental gems keeps expanding really fast, so we thought we'd release an update to send you down memory lane once more. Safe travels!

#1 Remember The Visualizer In Windows Media Player? I'd Spend Hours Staring At It

Image credits: ZaPandaz

#2 Who Else Remembers Cigarette Vending Machines That Had No Way To Check A Persons Age And Operated On The Honor System?

Image credits: FreeClownFarts

Even though we all feel nostalgia, it's not entirely clear what psychological purpose it serves. Is this longing feeling for the past good or bad?

Krystine Batcho, Ph.D., a professor of psychology at LeMoyne College, said the word was coined or invented a long time ago, over 300 years ago, and originally designated homesickness.

"Semantic drift over the centuries has broadened that to the notion of longing for or missing aspects of a person's personal lived past," Batcho explained.

#3 Robin Williams

Image credits: WhileFalseRepeat

#4 In The 2000's Everyone Had A Cd Case In Their Car Half Full Of Burned Cds, And It Was Better Than What We Have Now

Image credits: DoesThisMatter

#5 Multicolor Pens

Image credits: peter-s

"Most of the research available today including my research argues that nostalgia serves a number of functions," Batcho said. "The thing that ties them all together is that nostalgia is an emotional experience that unifies."

In other words, it helps to unite our self, our sense of who we are, and our identity over time. This can be valuable because over time we change in incredible ways.

"We're not anywhere near the same as we were when we were three years old, for example," Batcho added. "Nostalgia by motivating us to remember the past in our own life helps to unite us to that authentic self and remind us of who we have been and then compare that to who we feel we are today." This also gives us an image of who we want to be in the future.

#6 Magic Mitt For The 90s Kids Out There

Image credits: mcmcdonough

#7 The Art On The Back Of The Little Golden Book Series

Image credits: wileycoyotea

#8 Teacher's Pulldown Maps

Image credits: DualCay0te

#9 Remember When You Didn’t Have To Enter Your Personal Info Online To Win A Soda?

Image credits: tralletz

Nostalgia also serves an essential psychological function in that it's a highly social emotion. It connects us to other people.

"In the beginning, when we're very young, it's part of what bonds us to the most important people in our life, our parents, our siblings, our friends. As we go through life, it can broaden out and extend to a wider sphere of the people we interact with. It's a social connectedness phenomenon and nostalgia is in that sense a very healthy pro-social emotion."

#10 Robinhood Men In Tights (1993)

Image credits: Apprehensive-Mix2450

#11 Is It Me Or Did You Guys Have Those Temporary Trailers Attached To You're School That Were Only Meant To Stay Up For Like 3 Years But Ended Up Staying For Like 30?

Image credits: DudeThatsSpermNoMilk

#12 Having To Manually Roll Down/Up Your Car's Windows

Image credits: SharkPirateNinja

#13 Solitaire Card Backs

Image credits: AstroSlytherin

In itself, nostalgia is somewhat of a conflict because it is a bitter-sweet emotion. But that also has a hugely positive effect because it helps us to unify what otherwise would be felt or experienced by us as conflicts.

"The bitterness comes from the sense that we know for sure that we can never really regain them, they're gone forever. The irreversibility of time means that we absolutely cannot go back in time so it helps us to deal with the conflict of the bitter longing for what can never be again together with the sweetness of having experienced it and being able to revisit it and relive it again," Batcho said.

#14 Teacher's Grade Book

Image credits: RexLayne

#15 Before Cell Phones… Here’s How You Found Your Friends

Image credits: CharlieJ821

#16 Silly Erasers That Never Worked

Image credits: DualCay0te

#17 The Time When Transparency Was All The Rage

Image credits: 2ezyo

According to Batcho's research, nostalgia can be a stabilizing force and comfort us during times of transition.

"It's very difficult to grasp change, because in some sense, at a very deep psychic level, change threatens us," the psychologist explained. "It's a little frightening because we're not 100% sure that we can control it. One of the most important aspects of being a healthy human being is having a sense that you are in control of things. When things start to change, either very substantially, such as major events in a person's life, getting married or getting divorced, getting a new career, going back to school or graduating from school, it's comforting to have a nostalgic feeling for the past that reminds us that although we don't know what the future is going to bring, what we do know is that we know who we have been and who we really are."

#18 Winamp. Did You Have It?

Image credits: andreastman

#19 Having To Manually Turn Off Your Computer

Image credits: 1800generalkenobi

#20 Defragging Your Hard Drive

Image credits: DarthForeskin

#21 Wood Grain Pull Out Vhs Storage

Image credits: Toadman005

Nostalgia brings things back. It stimulates memories of the times when we were accepted and loved and this phenomenon is very comforting. Knowing that at some point in life we didn't have to earn our love can be very powerful. Nostalgia helps us realize that our parents, our siblings, or our friends simply loved us unconditionally. And these thoughts can work miracles on us when we're undergoing turmoil in our personal lives.

#22 Magic Slate Paper Saver

Image credits: Jfonzy

#23 Family: Why Do You Love Pizza So Much? My TV As A Kid

Image credits: Grave_Warden

#24 This Ride That Almost Killed Us All In The 90's

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#25 Limewire

Image credits: PooPb0i56

Batcho believes nostalgia might even have an element of infectiousness and wishes it was even bigger. To understand what she means by that, think of a group of people who have some shared experience.

"The best example of that is when a group of friends are reminiscing about their antics, the things they did as either teenagers or children or what have you. There it's a bonding experience. Another example of that is we know from current research that sports fans love to do that. They talk about the games that they enjoyed and when their team was victorious. When you have a common bond, it can be very infectious and it's like a domino one memory triggers another."

#26 My Daughter. Playing With Her New Tamagotchi

Image credits: RobertPaulsen39

#27 Breaking Your Fingers Trying To Open A School Bus Window

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#28 The Mac And PC Commercials

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#29 Movie Theater Carpeting

Image credits: DualCay0te

And the reason why she wishes it was more infectious is that this, let's call it, collective nostalgia can break down when you have a group of people who do not have shared experiences to be nostalgic about. Suddenly if you have one individual wanting to reminisce about their past but no one else in that group remembers those things or lived through those things, you might get things like a generation gap. Someone is talking about the 1950s and a teen says they can't even imagine it.

So when you think about it, r/Nostalgia is doing a beautiful public service. The subreddit is bringing together those who might not have anyone to daydream about the past with.