A tag cloud (word cloud, or weighted list in visual design) is a visual
representation of text data, typically used to depict keyword metadata
(tags) on websites, or to visualize free form text. Tags are usually single
words, and the importance of each tag is shown with font size or color.
This format is useful for quickly perceiving the most prominent terms and
for locating a term alphabetically to determine its relative prominence.
When used as website navigation aids, the terms are hyperlinked to items
associated with the tag.