* Defining a language: There's no clear-cut line between a language, a dialect, and a variety. Some linguists consider dialects of the same language if they're mutually intelligible, while others may consider them separate languages based on cultural or historical factors.
* Small languages: Many languages are spoken by only a few people and may be underdocumented or even undocumented.
* New languages emerging: Languages evolve and new ones can emerge, making it an ever-changing landscape.
Estimates:
* Ethnologue: This database is widely used and estimates around 7,100 languages currently spoken.
* UNESCO: The United Nations Educational, Scientific and Cultural Organization (UNESCO) estimates that there are around 6,700 languages spoken worldwide.
It's safe to say that there are thousands of languages spoken today, with the exact number being fluid and subject to debate.