Over the years, the look of new jeans has become more and more worn. People like the worn look even if they have recently purchased these pair of pants new. Therefore, many of the jeans manufacturers have been putting holes in the jeans and fraying the edges to make the new pair of pants look old and worn.
The fray on the end of the jeans are the loose strings that hang down from the bottom of the jeans. A common way to fray your own jeans include cutting the hem off at the bottom of the pair of jeans. Then pull the strings from the ends of the jeans. When you pull them down, this will give them a frayed look.