It means to finish off the edges of a piece of cloth so that it will not unravel.
Your sewing machine may have a 'serge' feature. If it does not (or if you are sewing by hand) you can still do it; just do as Rock said and finish off the edges so they will not fray (i.e., perhaps use a blindstitch).
Hi A blind stitch will finish off the edges but so will a simple zig -zag stitch. just run it along the outside edge tight enough to stop raveling but not too tight to cause the fabric to wave...If it is a small area or project, there is a product called "Fray-Check" that stops fabric from raveling. I use it on my wall hung art quilts...Donna
A serger is another type of sewing machine. It has 4 cones of thread on it. You can use 4, 3, or 2 cones. It also has a blade (or knife as it is called) that also cuts the excess fabric off as you sew. You sew like you would with a normal sewing machine. But the serger wraps the threads around the edge of your fabric. Looks just like store bought stuff. Gives it a nice finish & keeps it from fraying. Good luck.
Like Diann99 said a serger is another type of machine. A serger is also known as an overlocker.
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