1 · Garter stitch
Knit only Reversible Lies flatThe first fabric anyone makes, and still the right answer surprisingly often. Squishy, thick, completely reversible, and it will not curl at any edge. It also uses about a third more yarn than stockinette for the same area, and is roughly twice as wide per stitch as it is tall per row.
Good for scarves, blanket squares, dishcloths, borders on anything that curls. Counting rows: one ridge = two rows.