But when they are addressing smaller audiences using the @ symbol, they are more likely to use non-standard words such as "nah," "cuz" and "smh", according to the study by the Georgia Institute of Technology.
The study also found when people write to someone from the same city, they are even more likely to use non-standard language - often lingo that is specific to that geographical area.
He said the study helps explain a puzzle about language in social media.
"Since social media facilitates conversations between people all over the world, we were curious why we still see such a remarkable degree of geographical differentiation in online language," said Eisenstein.
"Our research shows that the most geographically differentiated language is more likely to be used in messages that will reach only a local audience, and therefore, will be less likely to spread to other locations," he said.
"People want to show their regional identity or their tech savviness, using Twitter-specific terms, to their close social network ties," said Umashanthi Pavalanathan, a Georgia Tech graduate research scientist who worked on the study.
Eisenstein has looked at popular Twitter word trends and their origins for the last seven years. He said the more he studies, the more he realises that Twitter users are smarter than most people give them credit for.
"In this sense, heavy social media users have an especially nuanced understanding of language, since they maintain multiple linguistic systems. They know to use each system when it's socially appropriate," he said.
The study is published in the journal American Speech.
