An emoji says a thousand words.

The little digital images are everywhere, from smartphone operating systems to social media and apps. We're obsessed, sending an emoji of a dancer next to a smiley face next to crying cat. How did these tiny images take hold of our lives?

See also: How to Enable Emoji on iOS

"Emoji are a great way to add personality to a text-based conversation," says Jeremy Burge, the founder of website Emojipedia. Like the name suggests, it's an encyclopedia for all things emoji, cataloging each creative symbol.

For the quick text generation, sometimes sending one tiny emoji is easier than typing up a response. Everything needs to be conveyed immediately, and nothing is smaller or more expressive than an image.

However, the psychology behind emoji obsession runs a little deeper. In February, Dr. Owen Churches, of the school of psychology at Flinders University in Australia, conducted a study on emoticons. His research showed that people reacted to emoticons the same way they would react to a real human face.

The human brain learned to recognize an emoticon such as ":-)" because it interpreted it so often. It had become a "culturally-created neural response." Churches believes the same reaction could occur with emoji, particularly the ones with faces, in the future.

"I would expect the response of face sensitive parts of the cortex to emoji would be very similar to that of real faces," Churches tells Mashable. From a vision perspective, emoji are similar to faces, more so than emoticons, he explains. This makes it more personal than just being a cartoonish image on a glowing screen.

The use of emoticons has also been scientifically proven to help boost communication. In 1996, researchers at New Mexico State University conducted an experiment in which they gave two groups of 12 people a task to solve together. The groups had to communicate via computers; one had the option to use emoticons, the other did not.

The study found that 10 out of the 12 subjects chose to use the emoticons when offered, and, overall, the entire group enjoyed the process more than the non-emoticon team.

Other studies have shown emoticons amplify whatever message we're trying to send. A sad emoticon makes a written message seem sadder, while the same is true for happy emoticons.

While the same study has not been conducted with emoji specifically, it's easy to hypothesize similar results. The generation that is growing up with emoji now is more likely to become comfortable with and attached to using the colorful icons.

Now, with the numerous emoji options, and the 250 new ones arriving soon, which emoji are we actually obsessed with? Data aggregation site FiveThirtyEight created a code to find out the most popular emoji used on Twitter, as of June 2014.

Hearts topped the list with 342 million tweets, followed by "Joy," a face laughing with tears coming out of its eyes, the "Unamused" face, the "Heart Eyes" face and the "Relaxed" face.

Emoji also pervade our culture. They're all around us, and our brain has learned to adapt to their popularity and create "efficient neural responses to these stimuli," Churches says.

In 2009, a Kickstarter project was successfully funded for there to be an emoji translation of Herman Melville's Moby Dick (called, of course, Emoji Dick).

NBA player Mike Scott covered his arm in emoji tattoos. TV shows like the millennial-leaning Girls make self-aware emoji jokes. Beyoncé recently released emoji-themed merchandise. Katy Perry made an entire music video for "Roar" using emoji as lyrics.

You can also legally threaten someone with emoji. They're part of the lexicon, an understood part of the language, no matter how silly they seem. They're also a universally understood mode of communication.

Emoji symbols originated in Japan in the late '90s. Though they vary depending on what platform they're used on (i.e., iPhone vs. Android), they still bear great similarities to one another.

So go ahead, put that smiley face next to a frowning face next to a ghost. It's the same in every language.

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