Language is constantly evolving. There are currently more than 7,000 languages spoken in the world, but, according to some estimates, at least half of those will be extinct or seriously endangered by 2100. With languages forming, changing, disappearing and being discovered, it’s hard to keep track of which came first. So, what is the oldest language in the world? As it turns out, that’s a complicated question with no single answer. 

Figuring out which language is the oldest is more complicated than it seems. “When people ask ‘what’s the oldest language?,’ what they're often asking is, ‘what's the oldest example of writing, and what language was used to write it?,’” says Gareth Roberts, an associate professor of linguistics at the University of Pennsylvania. 

Other ways to approach the question are: What’s the oldest language in a particular geographic region? Or what is the “most conservative” language—one that has changed relatively slowly over time, he explains. Today, we only know of an ancient language’s existence if we find evidence of it in writing—but that doesn’t necessarily give us an accurate picture. 

“People have been speaking and using signed languages for far longer than they've been writing,” says Claire Bowern, a professor of linguistics at Yale University. “It's possible that there were earlier writing systems that haven't survived. We only know about these ones because they were written on durable items—stone, clay and bone.”

Languages are constantly—but gradually—changing, Bowern explains. “Identifying the age of a language is not like saying how old a child is; there's not a defined ‘birth’ point,” she notes. 

What we do know is that prior to actual language being written down, proto-writing was a way to communicate limited information with simple written marks or pictures. “You could argue that certain cave paintings are a type of proto-writing,” says Daniel Hieber, a linguist who studies endangered languages. 

Another example is using symbols to document trade deals—like the number of items that have been sent to another group of people. “Over time, that symbol system of tracking trades is actually what developed into cuneiform”—an early writing system, Hieber says. 

As far as the oldest spoken language? “If we're looking for the languages that are spoken in the world today, and we want to say which of those was written down first, the answer would be Greek,” Roberts says. “That's the oldest example of writing where the language that happened to be written down at the time has a descendant which is still spoken today.”

If the question is what language has the oldest written evidence, then Sumerian and Egyptian are the likely contenders, says Roberts. Both languages emerged around the same time—toward the end of the fourth millennium B.C., or about 5,000 to 6,000 years ago.

Some of the earliest evidence of writing is in the form of cuneiform script, characterized by wedge-shaped marks pressed into clay. Cuneiform was initially created by the ancient Sumerians who lived in the Mesopotamia region of the Fertile Crescent situated between the Tigris and Euphrates Rivers—most of which is in modern-day Iraq. 

“There is a longer history of Sumerian cuneiform going back into its proto-writing,” Hieber says. “But they're not writing complete sentences at that point.” Although Sumerians also likely began writing in complete sentences first, there is older documentation of a full sentence written in Egyptian hieroglyphics. 

“It's quite possible that the first examples we have of writing are, in fact, the oldest examples of writing: Sumerian cuneiform [and] Egyptian hieroglyphic,” Roberts says. That said, they’re not the earliest languages. “Languages have been around for hundreds of thousands of years before that, most likely, or even, being very conservative, about tens of thousands of years,” he explains. Both cuneiform and Egyptian hieroglyphic do seem to have been invented from scratch, according to Roberts. 

The oldest known complete written sentence is in Egyptian hieroglyphs, Hieber says. It appears on the tomb of the pharaoh Seth-Peribsen, and translates to “He has united the Two Lands for his son, Dual King Peribsen.” Like this one, many of the earliest examples of hieroglyphic writing are found on the tombs of Egyptian royalty and elite citizens. The language consists of symbols that look like people, animals and objects which could represent sounds, objects or concepts. 

There's some debate over whether the Egyptian writing system began as cuneiform, Roberts explains. Though hieroglyphics weren't based directly on cuneiform, he says that it's possible that Egyptians observed cuneiform and thought, “OK, that's a good idea, we could do that in a slightly different way,” and they came up with their own writing system. 

“My impression," he notes, "is that the dominant view now is that [Sumerian cuneiform and Egyptian hieroglyphics] were invented more or less independently at a similar kind of time."