In many languages and scripts, some glyphs are a combination of others, such as accented letters: é is the pairing of e with the diacritic “acute” on top.

When designing fonts, instead of copy-pasting the contours of both e and the acute accent into é, the designer adds an anchor on the top of e and below the acute accent, where both should be connected or anchored to each other. Thus, both elements are “called” to form the character é, which becomes its components.