VOIP and IP Telephony

I am still learning about VOIP and came to know of an interesting concept. How IP Telephony and VOIP are not one and the same thing. Well, to give you folks an idea as to how IP Telephony and VOIP are different..
VOIP is the transmission of Voice over an IP Platform. The voice might actually have originated on a PSTN network, was converted to packets to be transported over IP Network, and might actually be handed back to PSTN. Hence, here, only a part of the transmission is over IP Network.
IP Telephony takes this a few steps further and talks about an end to end IP System, where voice is converted to packets at the point of origin and transmitted over an IP network. IP Telephony talks of Voice Clients and Voice Applications over an IP Network. The receiving end is either a IP enabled device or an IP Gateway.