Not long ago I ran a poll on this blog asking readers to tell me which yarns they looked for when purchasing their handmade items. The results weren't very surprising, most people listed wool as their most desired yarn with just slightly under that being no preference. Personally I have no preference which yarns I use to create projects as long as they feel good to my fingers, and glide easily on my hooks/needles.
There is a place where I do discern yarns and that is in their characteristics and how it will play into the piece I'm creating. For example, if I want to create a light airy piece for Summer, I'm certainly not going to use a wool yarn for that. Nor would I use a ribbon yarn to create a sweater intended to warm for the Winter. You get my meaning. If you're a yarn / fiber artists you may already know the characteristics of yarns, but if you're a purchaser of items, this may be very helpful to you when deciding on a piece.
Wool:: (this scarf was made with 100% wool)
Wool can have different characteristics depending on it's breed of sheep. It's warm, insulating, breathable, water-repellent, dirt-resistant and naturally flame retardant. It can absorb up to 30% of it's weight in moisture without feeling wet, but it's weaker when wet than when dry. Some wools are made machine washable by being treated to a superwash process. Some popular items for wool include sweaters, hats, scarves, gloves, coats, jackets etc.
Cotton:: (these washcloths are 100% cotton)
Cotton is usually machine washable and stronger when it's wet than when it's dry. It's heavy, absorbent, inelastic and unlike wool is non-insulating. Cotton has a tendency to stretch and/or shrink when washed. Some popular items for cotton include washcloths, tops, accessories etc.
Synthetics:: (this neckwarmer was made with 100% acrylic)
Synthetic referres to yarns that have been manufactured and have no plant or animal origins. Since they are created to mimic the characteristics of natural fibers they are usually durable, water-resistant, and strong. They are also non-breathable, and non-insulating. Many are machine washable, but very sensitive to heat. Most popular items such as sweaters, wraps, hats, gloves etc. can and are created with synthetics.
As a fiber artists it excites me to have the various options because the diversity allows me to make items for anyone. Some have plant allergies, some have wool allergies, some can't stand the feel of acrylic, some just want a blend that has the best of both worlds and some just want a great looking piece that works. Because I have so many options I can accommodate all.
Now you can make an educated decision on content based on your personal needs.