Google just added 13 new languages — Amharic, Corsican, Frisian, Kyrgyz, Hawaiian, Kurdish (Kurmanji), Luxembourgish, Samoan, Scots Gaelic, Shona, Sindhi, Pashto and Xhosa - — Amharic, Corsican, Frisian, Kyrgyz, Hawaiian, Kurdish (Kurmanji), Luxembourgish, Samoan, Scots Gaelic, Shona, Sindhi, Pashto and Xhosa to the language library.
Google uses two approaches to build the translator. One is scanning on billions of already translated written texts and then using machine learning to identify statistical patterns.
The other one is relying on people in Translate Community to help improve current Google Translate languages and add new ones. So far, over 3 million people have contributed approximately 200 million translated words.
For your interest, among those newly added language, Corsican which is spoken in the Island of Corsica, France, was Napoleon's first language.