Wi-Fi Direct is an emerging technology meant to meet the growing demand for easy, portable wireless network connectivity.
It's peer-to-peer wireless networking, which means that wireless devices such as notebooks,
Mobile phones, PC, printers etc. can "find" one another and establish wireless connectivity
without need of the presence of a wireless router, an access point, or wifi hotspots.
Wireless devices can now connect to each other directly
to transfer content and share applications quickly and easily.
Devices can make a one-to-one connection, or a group of several devices can connect simultaneously.
Connections based on the specification will work at typical Wi-Fi speeds and range, protected by WPA2. So the most significant difference between traditional ad-hoc wireless networking (traditional peer-to-peer networking) and Wi-Fi Direct is security,speed and range.
Typical Wi-Fi speeds, which can be as high as 250 Mbps, ranges up to 200 meters.
They can connect from just a few feet away, but also across a home.
Source:
https://wifi-direct.blogspot.in/
- - - Updated - - -
•Wi-Fi Direct is not the same as ad-hoc networking: The most significant difference between traditional ad-hoc wireless networking (traditional peer-to-peer networking) and Wi-Fi Direct is security. In Windows ad-hoc networks, the highest level of security supported is WEP in mixed client environments (Windows 7 will support WPA2 provided all adapters support it, as well). Wi-Fi Direct, as mentioned, supports WPA2. Another difference, Wi-Fi Direct devices can also simultaneously connect to existing wireless networks. More granular control and better discovery of devices also differentiate Wi-Fi Direct from ad-hoc networking.
source: http://www.pcmag.com/article2/0,2817,2371413,00.asp