= Font hinting
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<Font hinting> guides the adjustment of a scaled <outline font> to the target <pixel> grid before <rasterization>. In <TrueType>, instructions can control how outline points move at a particular size and resolution. <Grid fitting> can preserve important strokes when faithful geometric scaling would leave them awkwardly positioned between <pixels>.<TrueType Fundamentals by Microsoft>[From Font File to Paper; Instructing Outlines: scaling, grid fitting and scan conversion]{ref}
For an idealized example, two equal-width vertical strokes can overlap different fractions of neighboring <pixels> after scaling. Their rasterized darkness can then differ despite equal geometric widths. Coordinating the adjusted stroke positions and widths can make their displayed weights more consistent. The target depends on the requested size: a correction suitable for a small <glyph> need not be appropriate when many more <pixels> resolve its outline.
<Font hinting> changes the geometry used for rendering, rather than the underlying <Unicode> text or its <grapheme clusters>. <Glyph substitution>, <glyph positioning> and <font hinting> solve different parts of the path from encoded text to a visible image.
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