By default, type is displayed with the fractional widths option on. This option allows the spacing between characters to vary using fractions of whole pixels. In most situations, fractional character widths provide the best spacing for type appearance and readability. However, for type in small sizes (smaller than 20 points) displayed online, fractional widths could cause type to run together or have too much extra space, making it difficult to read. Turn off fractional widths when you want to fix type spacing in whole-pixel increments and prevent small type from running together. The fractional character width setting applies to all characters on a type layer