Mostly, the threads of polyester, cotton and poly-cotton are used for production of various fabrics. Whenever, you are on a sewing project, you should always ensure the content of fiber, while you select your threads. First of all, you must select a suitable colored thread, which harmonizes perfectly with the color that is dominant in the fabric. If you cannot find the perfect color, then you can procure the thread which is at least two shades darker than the dominant color of the fabric. If you procure a lighter shaded thread, then the stitches would be easily visible.
The cotton thread is superior to any other threads available in the market. If your fabric is medium weighted, then you can go for the cotton threads. If the fabric for which you are procuring the thread are not or less flexible, then cotton thread are optimum for them. If the fabric is very stretchy, then the cotton thread would break. If you have a flexible fabric then better use polyester threads. They are optimum not only for the hand stitching but also for the machine stitching. Fabrics that stretch a lot should be sewn with the polyester thread only. However, you must bear in mind that the stitches taken from the polyester thread would seem a little shiny.
Most people prefer a poly-cotton thread for most of their sewing projects. Thread like this is definitely multipurpose. In most of the fabric stores, you can easily find the poly-cotton thread. This thread is also suitable for sewing with both hand as well as machine. Fabrics which are delicately woven require the silk thread. Mostly undergarments are sewed with either cotton thread or silk thread. The silk thread is comparatively suppler than other threads; therefore, they are opted for if sewing is to be done of a very flexible fabric.
If the fabric that requires stitching requires some extra vigorous and durable stitches, then you should opt for those threads that are meant for heavy duty works. Metallic threads should be used for the work of embroidery, for both machine and hand sewing. However, you must confirm about the thread, weather it is suitable for machine sewing or not, before you use it with your sewing machine. There are special quilting threads available in the markets, which could be used for those projects which require machine or hand quilting. Other threads would slip easily, if they are not meant specifically for quilting.