You can add or reduce space between words (tracking) or between letters (kerning).
To specify tracking:
Type word-spacing: length, where length is a number with units, as in 0.4em or 5px.
Figure 10.27. Here I've added .4em of extra space between letters (which at a font size of 22px will mean almost 9 pixels between each letter).
To specify kerning:
Type letter-spacing: length, where length is a number with units, as in 0.4em or 5px.