Personally I would never correct someone - I know what people mean when they say "Fair Isle knitting," and I don't take it personally. But it's interesting to understand the difference between all the different kinds of colorwork. Learning to distinguish between the various forms is a worthwhile project in and of itself.
All of the things we'll be talking about in this article are "stranded knitting." Stranded knitting covers every kind of colorwork where you knit with two (or more!) strands of yarn at the same time, carrying the un-used strands along with you as you go.
(Things which are "colorwork" but not "stranded knitting" include intarsia and duplicate stitch.)
Fair Isle Knitting
Fair Isle is a tiny island in the Shetland island archipelago off the coast of Scotland. Traditional Fair Isle is worked in only two colors at a time, and use a limited palette with only 4-6 colors used in the work as a whole.
Fair Isle knitting is typically seen in sweaters, and the occasional hat. Traditional Fair Isle patterns often use the same collection of typical motifs, including OXO and little peeries between motifs. Typically all of the various patterns will be worked in the same shade of light-colored yarn (often white or natural), against a dark and colored background.
I call peeries "the little flecky bits." Peeries are mini-motifs to transition between two motifs. Something like 3 black stitches followed by 1 white stitch would be considered a peerie.
Nordic knitting patterns are characterized by snowflakes and frostrosen, the big snowflake-like flower that you often find on the back of mittens. Classic Nordic patterns are worked in only two colors throughout, usually with a dark pattern over a light background.
While Fair Isle patterns usually balance large motifs with small, I find that Nordic patterns often have a lot more white space. Followed by borders and patterned areas with a dense regular pattern, like the checkerboard on the palm of a mitten.
The Bohus tradition is a specific form of knitting (actually a brand name) which came from the small Swedish town of Bohuslan. During the depression, this town formed a knitting cooperative to knit and sell sweaters called Bohus Stickning.
Bohus sweaters are knit at a fine gauge, with a plain-colored body and arms. Only the yoke is patterned, but what a pattern! Many rows of Bohus knitting will have you carrying three colors, and sometimes even more. Typically the body will be a somewhat drab color like gray or olive green, to provide extra contrast to the yoke's stunning vivid colors.
Bohus sweaters were also sold as kits to knitters who wanted to make their own. The kit came with a finished yoke; just knit acres of plain stockinette, then graft a few hundred stitches together, and you're set!
Photo credit: Flickr/BloomKitty