Invisibility has always been one of the most popular of human wishes. Many scientists have experimented with invisibility without sucess, although films such as Die another Day, The Invisible Man and Hollow Man suggest otherwise. In theory one might be able to alter light waves in the same way as radio waves, or use a set of screens and cameras to display on the side of an object the background behind it (as for the Bond car), but these methods have never been effective in real life.
Ironically, according to the laws of physics, an invisible person should also be blind. In order for the retina to see, it must absorb light. But if a body is invisible (ie not absorbing light) how is it possible that the eyes still work in the same way?
J.K. Rowling uses invisibility in many instances in the Harry Potter series. In the first book, Harry is given an Invisible Cloak. Wizards and witches are able to make not only themselves but also solid objects invisible by means of a special 'charm'.