DocuBurst is a free web-based visualization tool for exploring the contents of a text.  Visitors can upload their own text or view those provided by others. DocuBurst presents an interactive chart called a ‘radial sunburst’ diagram which organizes the nouns extracted from the user-supplied text based on their meaning, and colours them based on frequency, revealing common themes in the text.  The visualization also shows the proper nouns (e.g. character names) in a linked word cloud. The visualization may be zoomed, filtered, or refocused to target types of words of interest (e.g. “animal” words or “feeling” words).  The visualization also provides a comparison tool to contrast word use across two documents.  DocuBurst views can be bookmarked, annotated, shared, and embedded in your own website.