The phone will talk when you input a text on... Like Microsoft Sam back in the Windows XP days.
It's kinda like when you get a text message and kinda lazy to read it, you can just let the phone read it for you.
Oh and if you come across certain words like, 'supercalifragalisticespi-whatever' then the phone might not be able to pronounce it right. So, just don't rely on TTS too much (especially if English is a Foreign Language)
