We've seen cloaking in iconic media like Ghost in the Shell and The Avengers, and of course the Predator franchise is infamous for the cloaking technology the Predator uses to hunt prey. We've even seen it used in Harry Potter, because the ability to turn totally invisible is exactly the kind of power you give to an adolescent boy.
As for real-life, while an invisibility cloak is not yet in production, cloaking technology has been in its nascent stage for the better part of three years. Scientists in the UK, in particular, have begun the first leaps toward unlocking the secret of cloaking technology. The science behind it is weird, complicated, and would probably take an entire academic career to explain, but in short: it uses optics and metamaterials to bend light away from the object, rendering it invisible to the naked eye.
While no prototype's been developed, the theory is there, it makes realistic sense, and that's more than enough to make it count. We hope to see this technology reach maturity and become available within the next ten years, but if pop culture is anything to go by, the military will get first dibs, leaving us to wait twenty or so years before we can get our hands on it. That is, presuming we survive the Great Invisible Nuclear War of 2040.