Chapter #32. Always Give Icons a Text Label
Now, I don't mean text on the icon (see #29 Don't Use Obsolete Icons)—I mean a text label near the icon, not just an icon on a button on its own. Small, nondescript buttons, with obscure mystery icons on them, are next to useless and consistently perform terribly in user tests. There are exceptions to this—frequently-used controls (like bold, italic, underline, and so on.) can be recognized without a text label, but icons in a main menu or toolbar really need descriptive text next to them.
Let's go back to the original purpose of the icon—to provide a quick visual shorthand by which the user can instantly recognize a control, and to provide a target for the user to click or tap. The icon isn't meant to describe a button the first time that the user sees it—the user will need a text label for that. However, if the icon is distinct and recognizable, then the user will locate the control and recall its purpose more quickly with an icon.