It should come as no surprise that the top three languages spoken in the world are English, Mandarin and then Hindi, with Spanish and French following in fourth and fifth place.However of the billion or so people who speak English, only 33% consider it as their first language.
However if you taken into account native speakers, then Mandarin Chinese shoots up to first place with its 918 million speakers, almost 2.5x that of English native speakers.
The diagram below from WordTips illustrates the 100 most spoken languages in the world, the number of native speakers for each language, and the origin tree that each language has branched out from. There are said to be just over 7,000 languages around the world, but this study looks at the top 100.
This could be why a large proportion of English native speakers often only speak one language. How many languages do you speak?