Dingbats are graphic typographical ornaments which are designed to be used as spacers in typesetting. The use of dingbats can help a printed document feel less blocky and overwhelming, and they can be used to add a note of humor or sobriety to a piece, depending on the dingbats used and how they are utilized. A number of companies produce dingbat fonts, large collections of dingbats for use in computerized typesetting, and several foundries continue to cast dingbats for letterpress printers.
The history of typographical ornaments is quite old. Almost as long as people have been writing, they have been decorating their printed material with ornaments of various forms, and when the printing press was developed, dingbats were not far behind. In addition to serving a purely aesthetic use, dingbats can also be practical, breaking up the visual space in a printed piece and sometimes being used as symbols to indicate various things.
Dingbats come in a wide variety of styles. Many are designed along floral themes, in which case they are known as fleurons. Others take the form of small animals, while some are geometric in design. A number of dingbats are also designed to work as symbols, coming in forms like pointed hands, bullets for text, and so forth. Many modern dingbat sets include various computer-related symbols.
If you have printed material around you, you can probably find an example of a dingbat. Dingbats lurk between paragraphs, at the edges of pages, and sometimes in the upper corner of a page near the page number. You can see some rather florid uses of dingbats and eccentric fonts in 19th century printed advertisements and information posters, when printers sometimes erred on the side of garishness to get the point across.
As trends in typography change, the use of dingbats also changes, with some periods being marked by relatively austere typesetting, and others with explosions of dingbats, borders, and other ornamental features. You may find that the use of dingbats in your own printed materials can change the mood of the material dramatically, and dingbats can be advantageously used to add space, to delineate different sections in a piece, and to draw attention to a particular area of interest. Most computers come with several default dingbat fonts such as Wingdings and Webdings, and you can also find more from font manufacturers. A number of dingbats also come with their own Unicodes, like this one: ✿.