The Holoband is brought to you by the same Graystone Industries that gave us the Cylons. Their more benign product is, as the name suggest, a band that creates a holographic projection of sorts. The band is worn around the head and eyes much like a pair of glasses. When activated, it projects and artificial virtual world into the wearer's mind. This world can be limited to singular programs or to a much larger massive online virtual community as limitless as the Internet.
The holoband can be used as a tool for work although it is more commonly used for recreation (with many getting lost in how very real it can seem). The Holoband is also a very useful tool to create simulations, something which has not been lost on the military. Recruits, especially potential pilots, go through portions of their training on holoband. Generally this will be their first taste of training before being let out to use "the real thing" which happens to be a very dangerous and expensive piece of equipment. The more dangerous aspects of training (the types of things that if one were to actual do it live would be considered completely reckless and even potentially criminally so - e.g. live bomb defusal) can also be performed at the end of training, or even beyond in further education, through the holoband.