An icon of a diskette still conveys the “save” function, even though nobody uses diskettes anymore and the youngest computer users are unaware of what a diskette really is. Icons convey immediate meaning and provide shortcuts to it. Reading text requires more energy than deciphering an icon.
Icons can be used to allow for scanning and increase readability. Use icons to indicate the beginning of new paragraphs.
Icons can be used to set the mood, personality, and general atmosphere of a website. Consider the theme of your website and choose icons accordingly. What style does your site have? Mordern? Classic? Slick? Web 2.0?
Enough talking – check out these 63 great uses of icons in web design