Wi-Fi Direct, initially called Wi-Fi P2P, is a Wi-Fi standard that enables devices to connect easily with each other without requiring a wireless access point and to communicate at typical Wi-Fi speeds for everything from file transfer to internet connectivity.
Wi-Fi Direct essentially embeds a software access point ("Soft AP"), into any device that must support Direct. The soft AP provides a version of Wi-Fi Protected Setup with its push-button or PIN-based setup. When a device enters the range of the Wi-Fi Direct host, it can connect to it, and then gather setup information using a Protected Setup-style transfer. Connection and setup is so simplified that some suggest it may replace Bluetooth in some situations.