DTMF In band and Out of band - what is the meaning

[nekote]

I may have a DTMF issue.

I would like to better understand what In-Band and Out of Band means.

In-band meaning transmitted over the regular audio channel that the far end hears us on?

Out of Band some Telco special auxiliary / side bandwidth?

[QBZappy]

DTMF: In-band & Out-of-Band
http://forums.whirlpool.net.au/archive/725830