Hint, Hint: Because of rounding errors, a font outline won’t give the perfect pixel pattern at every size. In the middle “m” above, rounding errors cause the first stem to be two pixels wide, while the second and third stems are only one pixel wide; there’s also a gap where the second arch joins the middle stem. Software that ­corrects for rounding errors, a process known as hinting, creates the bottom “m” by ensuring that the stems and arches have the same width.