Greek is forever alone.

I'm surprised at how many people in the Facebook comments aren't understanding what this diagram means. I guess I'm unusual in having such a fascination with linguistics that I've known about this since I was about 12.

The diagram shows some of the languages in the Indo-European language family, the largest in the world, both in terms of population speaking one of these languages and land covered. However, there are many more language families, and most languages are in one of those (439 languages in this family out of over 6,000 languages in the world). I'm sure this is all on Wikipedia, people. From there, the biggest nine families by percentage of world population:

1. Indo-European languages 46% (Europe, Southwest to South Asia, North Asia, North America, South America, Oceania)
2. Sino-Tibetan languages 21% (East Asia)
3. Niger–Congo languages 6.4% (Sub-Saharan Africa)
4. Afro-Asiatic languages 6.0% (North Africa to Horn of Africa, Southwest Asia)
5. Austronesian languages 5.9% (Oceania, Madagascar, maritime Southeast Asia)
6. Dravidian languages 3.7% (South Asia)
7. Altaic languages 2.3% (Central Asia, Northern Asia, Anatolia, Siberia)
8. Austro-Asiatic languages 1.7% (mainland Southeast Asia)
9. Tai–Kadai languages 1.3% (Southeast Asia)

They list 157 families in total, although who knows if the list is either accurate or complete.