What effect has the internet had on comedy?

"The internet is made of cats," Huffington Post co-founder Jonah Peretti once told me. He was, of course, referring to the frankly obscene number of pictures and videos of cats in ridiculous situations, wearing silly outfits, doing hilarious things that are littering every corner of the web.

If the hype is to be believed, cats are the epitome of modern web humour. They are the eternal subject of silly, one-click laugh fodder, from Maru, the Japanese YouTube kitty superstar most famous for jumping in and out of cardboard boxes (91m views) to the cast of thousands photographed in compromising positions and labelled with poorly spelled captions on the internationally lauded icanhascheezburger.com. But these moggies are more than memes. They explain why we are able to relate to one another online.

It's not surprising that so much of online content is comedy; the library of psychological and anthropological research describes humour as the glue that helps to define communities and keep them together. Psychologist Dr Rod Martin, who has published extensively on the role of humour in mental and physical health, describes it as a coping mechanism: we seek to clarify a unified reality through our interpersonal communications, but when that unified reality isn't forthcoming – because we inevitably look at the world through different frames of reference and have different interpretations of what's happening around us – we poke fun at our inconsistencies, which allows us to smooth them over because we are able to embrace the contradictions.

It's also an essential part of our social development. From a young age, we are influenced by what our social group defines as funny. We conform to that for the sake of keeping the peace, to feel like we belong, and to function to our greatest capacity in our small section of the world. Now, we share much of our online interaction on social networks such as Facebook with people we know, in an environment that sociologist Ray Oldenberg would call a "third place": a space such as a cafe or pub, where we can extend the bonds we have with one another through light-hearted, often humorous interaction.

But beyond Facebook, the web is still an overwhelmingly anonymous place. It has historically had so few default social cues that we've spent much of our online time asking one another, "Age/Sex/Location?" to identity the most appropriate way to chat. Humour gives us, the anonymised strangers, instantaneous common ground. And that explains why social scientists and communication scholars have found so much banter in our everyday online conversations.

It also explains the ephemeral and quick-fix nature of most online comedy. Let's face it; LOLcats and a Japanese moggie jumping into boxes aren't exactly high-brow. But across the ocean of possible new friends online, they are the only cornerstones we have to establish connections between one another, and to find people like us. We rely on universals. One of these, in the early 21st century, appears to be cats.

Professor Jim Hendler, a veteran of the internet of the 1970s, says that "second perhaps to pornography, humour was a major force" in the first two decades of the net. "The kind of humour that worked best online in the 70s and 80s was counter-cultural stuff that chimed with the nature of what we were doing," he says. "Those of us using email lists on the ARPAnet were hiding the fact from our advisers. Cats really came into the story with the addition of images and web technologies."

The limitations of the medium – when a computer screen only had 20 lines of 80 characters – also set the scene for the format of what works in modern online comedy. "Reading anything long took a long time and was boring," says Hendler. Now that we have images, audio and video, successful jokes and puns are even briefer, a feature that Martin Trickey looked for as one of the BBC's comedy commissioners for multi-platform.

Trickey has identified four characteristics that work: brevity, topicality, authenticity and self-containment. "You don't need to know anything about where it came from or where it is going," he says. What this translates into is quick hits, rather than ongoing vignettes. "The attention span of the online audience is incredibly short. If we haven't got you in the first 10 seconds, we have probably lost you. It makes character development difficult and long-running narrative impossible."

Hence the reliance of most successful online humour on current events and what can appear to outsiders as a series of in-jokes. Importantly, although they may not look like the pinnacle of cultural sophistication, these jokes are transformed into postmodern satire and parodies, as people develop derivatives. They become the bedrock for culture.

Although rare, some comedians are able to foster ongoing relationships with their audiences. Peter Serafinowicz has used YouTube and Twitter for self-promotion and to play with different ways of being funny. "Immediately you've got a huge audience, and not just locally, but globally," he says. The videos he published with his brother James raised his profile in the US significantly, and won him a TV contract with Channel 4.

Serafinowicz has also relished the interactivity of a medium such as Twitter, which he says replicated, in some ways, an offline, live experience. "Twitter is very satisfying for a comedian: to think of a funny quip, to put it up, and to have people re-tweet it or react to it." He also loves how the 140 characters forces him to think shorter. "Brevity is the soul of wit," he says. "It's really helped me hone my one-liner skills."

As humans, we grasp commonality, and share what we find funny with our group to demonstrate our belonging. Now, thanks to the rise of social networks, little memes can spread like wildfire, and can be adapted and transformed. The pervasiveness of silly pictures of cats is simply our way of creating a unified reality out of nothing. Humour is the heart and soul of the web. It makes it the place we want to be.