Tags in research

A researcher may work with a large collection of items (e.g. press quotes, a bibliography, images) in digital form. If he/she wishes to associate each with a small number of themes (e.g. to chapters of a book, or to sub-themes of the overall subject), then a group of tags for these themes can be attached to each of the items in the larger collection. In this way free form classification allows the author to manage what would otherwise be unwieldy amounts of information. Commercial, and some free, computer applications are readily available to do this.

Tags within a blog

Many blog systems allow authors to add free-form tags to a post, along with (or instead of) placing the post into categories. For example, a post may display that it has been tagged with baseball and tickets. Each of those tags is usually a web link leading to an index page listing all of the posts associated with that tag. The blog may have a sidebar listing all the tags in use on that blog, with each tag leading to an index page.

To reclassify a post, an author edits its list of tags. All connections between posts are automatically tracked and updated by the blog software; there is no need to relocate the page within a complex hierarchy of categories.

History and context of tags

Labeling and tagging are carried out to perform functions such as aiding in classification, marking ownership, noting boundaries, and indicating online identity. They may take the form of words, images, or other identifying marks. An analogous example of tags in the physical world is museum object tagging. In the organization of information and objects, the use of textual keywords as part of identification and classification long predates computers. However, computer based searching made the use of keywords a rapid way of exploring records.

Online and Internet databases and early websites deployed them as a way for publishers to help users find content.

Read more: History and context of tags