I have had a serger for years, and now have Viking 936 - 5 thread model. I need to learn more about it - not only for ME, but for training the teachers in my district. We have purchased sergers for the high schools, and are getting them in the Jr.Highs - and the teachers are TERRIFIED!! I know what a wonderful and useful tool sergers are, and having books to show them will make it more useful and fun, so they can encourage another generation to love to sew and serge.