Way back in the day when I first joined, we had a built in dyes program called foxdye. If you talk to Anne the Stylist inside of Prontera's bottom left building, you will see that you can change clothing colors, but when you leave, they change back to the basic one. What dyefire and dyeadvance do is allow you to see those colors, along with the colors other players have chosen. It's a fun program to use.