Encyclopedia of Social Network Analysis and Mining

Abstract

A Tag Cloud is a visualization method that summarizes a set of tags related to a certain resource or a set of resources in a visually appealing manner. Contrary to a word cloud, the tags in the tag cloud are generated by people and refer to resources through links. Usually, a tag cloud shows the top most N tags of one particular online resource, a set of resources or the resources of the whole system. A very basic and at the same time very popular approach for tag clouds calculation is an algorithm that sorts the tags by alphabet and indicates the importance of each tag by font size (see Figure 1). However, today a large variety of tag cloud calculation algorithms exist. Some of them display tags in different colors, some of them cluster tags into categories (see for example Figure 3) or according to their semantic meaning, while others manipulate the font, the intensity of the tags or simply display the tags as a list [1; 4].