Sewing Basics - Wovens versus Knits

Fabrics are a bit of a mystery to me. Which is rather funny since the job I work in is highly related to textiles and many of the individuals in my group have a textile degree of some sort.  But I am guessing that aside from this group of persons I work with, many others out there are trying to learn the basics about fabrics that they use in their own sewing projects (or maybe I'm the only nerd out here).

Most of the fabrics I've encountered are either woven or knit (as opposed to crocheted or spread, etc).  Woven materials are woven on a loom. They have threads that run the entire length of the material roll (this is the warp) and then there are other threads that are woven through/across the warp threads (weft).  Generally these materials will have an edging down the two of the sides. This is called selvage and it runs in the direction of the warp (thank you work friends for teaching me these items). Wovens are generally not stretchy and wrinkle like crazy (this is why I have to iron so many fabrics for my projects)!!. And the unsewn edges seem to fray terribly unless measures are taken to prevent fraying (eg. cutting with pinking shears).

Wovens include material like:  Silk, Satin, Canvas, Corduroy, Linen, Muslin, Cashmere

Knit materials are a bit different though. Instead of being woven on a loom, they are knitted on a machine just like one would knit by hand. Knit materials are generally stretchy unlike woven materials. These materials are also wrinkle resistant. These materials are broken into two types of knits: warp-knitted and weft knitted . 

Weft knitted fabrics will run (or can run) when they are cut. These type of materials are used in things like lingerie. A hand knitted sweater would also be considered weft knitted. Warp knitted fabrics typically don't run. Warp knitting is not done by machine only.

Knits include: jersey, felt, mesh

There is a great article at Threads Magazine that tells you how to determine if a material woven or knit when you are in the store. See that article here.

In the article they tell you to (1) look for the grain, (2) stretch the material, (3) test for wrinkles and (4) look at the edge of the material.

 So good luck on your next trip and I hope you now know a little more than you did 5 minutes ago. ;)