India entered the age of "talkies" in 1931, with the release of "Alam Ara". This set off the
regional trend that continues to the present day: Movies are produced in any number of regional
languages as well as the common Hindi language.
Another key component of Indian films was a natural outgrowth of sound: music! Early talkies had as many as 40 songs. That number has gone down somewhat, but music, song, and dance remains important to all mainstream releases.