Actually, the window air conditioner is a tiny unit and it specially made to fit the standard window space. They also works like any other AC unit and they usually come in diverse British thermal units capacities to cool the rooms of different sizes. At present, the air conditioner window unit came to the market as a solution for those who could not even afford or do not require the central air conditioning. This is because; the central air conditioning can be fairly costlier and most of the people live in tiny apartments and the central AC unit is not for all. This would lead to the beginning of window air conditioners.