Wearable Technology is a category of technology that can be worn on the body. The devices and gadgets in the clothing tend to be connectable to the Internet, Wifi and/or other Bluetooth devices.
Wearable Technology is another one of those technology sectors that tends to be created almost entirely from existing technologies already developed for other uses. Sensors, transmitters, receivers and even fabric technology tended to already exist in forms for other purposes and yet extend to what we wear.
As with most definitions, what exactly qualifies as Wearables differs depending on your perspective. For exponential technology purposes, anything you attach to your person can well be considered wearable tech.
The more obvious things such as the iWatch, and a wireless wardrobe of fancy fabrics. There are visions of comprehensive integration of robotics for amputees and augmentation for the rest of us.
Here is a great video by Hugh Herr providing some insight from the most basic to the extreme edge of technological advances from his own unique experience: