What are hems? How can they affect a garment's appearance?

 A hem is the edge of a piece of cloth that has been folded, pressed, and sewn. This is to give a neat finish to the edge of the fabric and also prevent the fabric from fraying or unraveling. Hems may be sewn with an invisible stitch called the "blind stitch", or sewn with a sewing machine. Decorative embroidery is sometimes called hem-stitch design. Other methods of  securing a hem call for no any sewing at all but instead using clips, netting, iron on materials, and other kinds of fasteners. These kinds of thread-less hems are not very common, and are used mostly for temporary use. The hem's seam allowance effects the way the fabric on the finished fabric will drape. Heavier fabrics require more of a shorted hem. A "dressmakers hem" can also be used when working with heavier fabrics; an extra line of loose running stitch is added in the middle of the hem, so that all the weight of the cloth does not hang from one line of stitching. Modern sewing machines designated for home use come equip with decorative and functional stitches that make the number of possible hem treatments large.

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