Used in reference to computer based recording systems. In the early days of computer recording, much of the processing work had to be done on additional hardware cards, while the computer merely provided visual feedback. But because of the unprecedented power that is available in today's computers, it is entirely possible to have a virtual studio within the computer, using only the computers processing power. Host based systems are still hampered to some degree when compared to their hardware card equivalents, but as computer power increases, so host based systems become more and more economical.