Some people out there on the web spend their time inventing artificial human languages. I wonder what they do with it. With natural human languages (the kind discussed here) there's usually plenty to do. Nevertheless, it is sensible to first check the number of speakers, wether or not you'd like to travel in the countries where it's spoken and the kind of culture (books, movies, songs, etc...) that is available. Italian scores high on all of this, twi (an african language) is more problematic.

A. Number of speakers

The first thing many people ask is how many people speak their target language. Of course this is important but can be misleading. After all if size was all we would all learn chinese and live in Texas (where they like big things). Actually, I suggest you consider size after other considerations, like usefulness or travelling opportunities. Nevertheless for those of you who think they should aim for the biggest, I give you a somewhat old table of the top league :

©	Language	Speakers
1	Mandarin	1'000 mio
2	English	600 mio
3	Hindi-Urdu	420 mio
4	Spanish	330 mio
5	Russian	285 mio
6	Indonesian	190 mio
7	Portugese	175 mio
8	Arabic	170 mio
9	Bengali	150 mio
10	French	130 mio
11	Japanese	125 mio
12	German	100 mio

Total number of speakers, as a mother tongue
and as a second language