Translations:AY Honors/Knitting - Advanced/Answer Key/32/en
From Pathfinder Wiki
Unlike other multicolor techniques, there is only one "active" color on any given stitch, and yarn is not carried across the back of the work; when a color changes on a given row, the old yarn is left hanging. This means that any intarsia piece is topologically several disjoint columns of color; a simple blue circle on a white background involves one column of blue and two of white---one for the left and one for the right. Intarsia is most often worked flat, rather than in the round. However, it is possible to knit intarsia in circular knitting using particular techniques.