Tracking the space between letters

Tracking is when you adjust the space between a selected range of characters. Instead of applying an individual amount between a pair of letters, tracking applies the same amount to all the characters that are selected. Because tracking does not take into account the shapes of the letters, it’s only useful to get a start on adjusting the space—you still need to fine-tune with manual kerning.

Any tracking you apply is added to the manual kerning and to the auto pair kerns. That’s why you might select an entire word and apply one value of tracking, but when you click between two characters in that same word, the Kerning field displays a different value. But the Tracking value does not affect the Kerning value! You can manually kern between individual characters until they are visually consistent, then apply tracking and everything will tighten or loosen proportionally.