A 3d printer is a printer that uses inkjet technology to print 3d objects, that is, objects that you can pick up and throw against a wall. The printers cost roughly (depending on how fancy they are) the price of a mid range porshe, and can be found at most colleges and universities with significant art or science/engineeering programs. I happen to be a mechanical engineering major at a community college known for it's engineering transfers, and the engineering dept. just got a printer last year. I don't know how available they are for the general public, but I know that because I'm taking a course which involves using the printer, I now have access(with permission) to that printer. They print in a variety of mediums, but most common is plastic, so the finished object is made of hard plastic. Hope that answers most of your questions.