I wanted to know what the difference is.
Chanting is Sprechgesang. My dictionary told me that sprechgesang is also an English word. Chanting is between speaking and singing.
It is possible to take any text and to chant it (even poems by Heinrich Heine).
Rappers chant. Chanting is rap music.
The function of chanting in the beginning of yoga is to get to the mat mentally, I heard.
For myself chanting "aum" is what I love most. (Remark: it is not ohm, but aum). The whole body vibrates and wakes up. The whole body gets the message: now is yoga time.
I do not chant in order to pray to someone. The whole practice is a prayer, I once heard.