The r/FoundPaper subreddit celebrated its 7th birthday a few days ago, on April 30 (congratulations!), proving that communities thrive and survive based on the quality of the content they post. And the fact that the subreddit has had so many birthdays is proof enough that it’s got quality entertainment locked down tight.

One of the ‘Found Paper’ community’s greatest strengths is how streamlined and niche its interests are. Its second strength is that it actually encourages its members to get out of the house and start their own small adventures in order to have something to post.

“Photographs of found pieces of PAPER(!) with writing on them. Look for paper, make every day a scavenger hunt. Appreciate the forgotten artifacts of everyday life. Share any paper that you found (on the ground, stuck in some bushes, or between cans of soup at the store for example) and you do not know who wrote it,” the subreddit’s moderators explain what their community is all about.

“Love letters, doodles, interesting to-do or grocery lists, notes from the past—share your discovery with us!” the mods encourage book, paper, scavenger hunt, and adventure lovers to share their awesome finds with everyone else.

The moderators also highlight the fact that in order to post any photos, the paper has to be found and it has to be paper. No forgotten plastic from your garage. No granite engravings from your neighbors Tom and Jane’s farm (because you know exactly whom they belong to and, well, paper beats rock).

What’s more, the mods want everyone to be “courteous and friendly” toward one another, avoid being “overly annoying or bothersome,” embrace tolerance and sensitivity, as well as remove any and all sensitive personal info from the photos before posting them. Sounds simple enough and it’s the basis for the rules most larger subreddits follow. Disruptive, chaotic, and intolerant communities don’t tend to last for long on Reddit (unless they’re doing it on purpose for the sake of humor).

The Library of Congress explains that how quickly paper deteriorates depends on its quality and in what environment it’s stored. Some ancient tomes and documents can actually be in far better condition than a scrap of paper that’s just a few years old.

“Paper is made of cellulose—a repeating chain of glucose molecules—derived from plant cell walls. One measure of paper quality is how long the cellulose chains, and subsequently the paper fibers, are: long-fibered paper is stronger and more flexible and durable than short-fibered paper,” the LoC points out that not all paper is created equally. If you’re going for longevity, long-fibered paper is your best bet.

Acids from the environment (like from air pollution or poor-quality enclosures) or from within the paper cut these glucose chains into shorter and shorter lengths in the presence of moisture. “This acid hydrolysis reaction produces more acids, feeding further, continued degradation.”

One of the reasons why newspapers don’t last for long is because they’re printed on mechanically pulped paper, meaning the paper has got the shortest fiber length. Meanwhile, the lignin from the wood isn’t removed (as in the case of chemical pulping) and promotes acid hydrolysis, shortening the glucose chains even more.

What’s more, it’s not just acid hydrolysis that threatens a piece of paper’s structural integrity. It can also be damaged by light (what’s known as being susceptible to photolytic degradation) and oxygen (oxidative degradation).

The poorer quality of the paper, the more light degradation affects it. Meanwhile, oxygen degrades paper in a very limited way, unless there are nitrogen oxide pollutants in the air.