* Defining "active" is difficult: What constitutes an active language? Is it a language with native speakers? A language used in education? A language with a written form?
* Language boundaries are blurry: Languages evolve and change, making it hard to draw clear lines between them. Dialects can be considered separate languages by some, while others might see them as variations of a single language.
* Ongoing research and discoveries: New languages are still being discovered, and some languages are revived after being dormant.
However, estimates range from 6,000 to 7,000 active languages in the world. This number is constantly fluctuating, and it's important to remember that it's just an approximation.