The term "dry" in drycleaning refers to the fact that there is virtually no water or moisture present during the cleaning process. Your garments are processed in a liquid, yes, but the liquid contains almost no water at all! Why no water? "Dryclean Only" garments are typically made of fabrics that are susceptible to damage by moisture. Wool, silk, and rayon are common dryclean fabrics that, if washed in water would shrink, mat, or lose strength while wet or when put into a tumbling drier, like the one in your home.
The loss of color during washing is another problem that is solved by drycleaning. The liquids used are far less likely to dissolve the dyes used to color your clothes. I'm sure you've washed a new pair of jeans and noticed the difference in color even after one washing. This effect may be desirable on your jeans, but certainly is not on your vivid red silk blouse, your new wool suit or your cashmere sweater, items that just cannot be properly cared for at home.
Modern drycleaning machines also use a process we call dry-to-dry. This means the garments are placed in the machine dry, are cleaned by a total immersion process in the drycleaning fluid, and then spun and dried. All this happens in the same part of the machine, similar to the basket in your clothes drier or a front-load type washing machine at your home. The difference is that the garments do not go from a "washing machine" to a "drying machine", it all happens in one machine! Another big difference is that the liquids used to clean your clothes are simultaneously being filtered during the cleaning process. So, unlike your clothes in your washing machine at home, the liquid itself is being cleaned the whole time your garments are being cleaned in it.
Finally, the liquids are continuously filtered and distilled right in the single machine, unlike your home washing machine that flushes many gallons of dirty, soapy water down the drain. Your professional drycleaner is recycling their cleaning fluid using modern equipment that brings the liquid back to it's "virgin" state during and after each load. These rather complex pieces of equipment require a significant initial investment and regular preventative maintenance, just like your car, in order to maintain a high quality.
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