Here are the major stringing materials along with how and when to use each of them.
SILK THREAD: Silk has a wondrous “hand” (a soft, flexible feel). This thread comes in many sizes and colors. It comes packaged on spools, and “carded” with an attached needle. This is a classic stringing material and forms beautiful knots between pearls and beads. But, silk tends to be relatively fragile. It can stretch, be cut by abrasive beads, rot when wet, and pearls strung on silk should be re strung every few years. It is best to use silk when stringing pearls and lightweight, smooth-holed beads, only. A needle is necessary.
NYLON THREAD: (Nymo): This thread also comes in many sizes and colors. It comes packaged on spools, on bobbins, and “carded” with a needle attached. Nylon can be used where-ever silk can and is not as fragile. This material knots beautifully and can be used for pearl stringing, in some strung jewelry, seed beadwork, loom weaving, for Peyote and other specialty stitches, and heishi. Nylon stretches much less than silk, and it won’t rot when wet. Like silk, you shouldn’t use beads with sharp edged holes or that are heavy. When you use nylon thread, I would recommend you coat your thread with bee’s wax or “Thread HeavenTM “ before use to prevent it from fraying. A needle is necessary.
BONDED NYLON: This is a much stronger form of nylon thread. The strands are physically bonded together for extra strength and abrasion protection. Although it knots well, it doesn’t have the “hand” of silk. Bonded nylon comes in a variety of colors and smaller spools. Because of its abrasion resistance, you can use it with “hard”, more abrasive gem beads; in fact this comes close to being a “Universal Thread”. Brand names include: “Stringth” or “Silkon”. A needle is necessary, although you can put “Super Glue” on the end to form a “Self-needle”. This is a favorite beading material of mine.
FISHING LINE: This material is a hard, semi-rigid, single strand of plastic. It doesn’t knot well, and in time sunlight or ultraviolet light can cause it to weaken and fall apart. Fishing line is purchased on small spools and is sold in sporting goods stores. Personally, I use fishing line for two purposes. I use it to do my preliminary stringing while I am designing a necklace (I transfer the beads to a better material for the final product), and to string together “raw” strands of beads. There is no needle necessary. I would never use this material for a final beaded piece.