* Defining "language" is tricky: Is a dialect a separate language? What about sign languages? How do we classify languages that are mutually intelligible?
* Data is incomplete: Some languages, especially those spoken by smaller groups, are under-documented or not fully recognized.
* Languages evolve: Languages constantly change, and new ones emerge over time.
However, estimates range from 6,000 to 7,100 languages.
Here's a breakdown of the major sources:
* Ethnologue is a widely used resource that lists around 7,151 languages. This includes many dialects and languages with limited documentation.
* UNESCO estimates around 6,700 languages. They focus on languages with a significant number of speakers and more readily available data.
* Other sources might use different criteria and come up with different numbers.
Important Note: It's crucial to remember that these are estimates, not exact figures. The number of languages in the world is constantly shifting and evolving.