Big wave HI......from middle Tennessee, and a big welcome!!! Quilting thread is a heavier weight thread,used mostly for hand quilting and sometimes machine quilting. Dual duty is used for piecing quilts and general sewing, it is a finer/lighter weight thread. If you use the quilting thread in your machine remember to change your needle to a larger size and adjust your tension or you may have problems sewing with it. Hope this helps and always ask questions and don't feel dumb for asking them,okay??? MAWLUV