This information provided by the United States Racquet Stringers Association. Softer strings, or strings with a softer coating, tend to vibrate less. Thinner strings tend to produce more spin by biting the ball more. Multifilament strings are more elastic than solid core strings. Solid core strings are more durable than multifilament strings with kevlar string technology being the most durable.
Kevlar strings are the stiffest and least flexible.
Multifilament strings play better than solid core strings. Multifilament strings lose tension more quickly than strings with a center core. Textured strings tend to produce more spin. Gut strings hold tension the best. Gut strings are the most fragile strings comparing to other similar gauged strings.