In information systems, a tag is a keyword or term assigned to a piece of information. Tags are generally chosen by the item’s creator.Tagging was popularized by websites and is an important feature of many websites. People use tags to aid classification and indicate online identity. The use of keywords as part of an identification and classification system long predates computers. Some desktop applications and web applications feature their own tagging systems such as photo tagging.
The photos found via the tags on this page include flora and fauna plus abstract photos of various types.
A tag cloud or word cloud is a weighted list of text data. 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. Also for locating a term alphabetically to determine its relative prominence. These clouds are to visualize the frequency distribution of keyword metadata content. They are also used as an navigation aid. The first tag clouds on a high-profile website were on the photo sharing site Flickr.
Photo Gallery Tag Cloud
Tag clouds have been subject of investigation in several usability studies. The following summary is based on an overview of research results given by Lohmann et al.
Tag size: Large tags attract more user attention than small tags (effect influenced by further properties, e.g., number of characters, position, neighboring tags).
Scanning: Users scan rather than read tag clouds.
Centering: Tags in the middle of the cloud attract more user attention than tags near the borders (effect influenced by layout).
Position: The upper left quadrant receives more user attention than the others (Western reading habits).
Exploration: Tag clouds provide suboptimal support when searching for specific tags (if these do not have a very large font size). WikipediaTag Cloud