| Social bookmarking sites generally organize | | | | classification software, such as search |
| their content using tags. Social bookmarking | | | | engine spiders. All tag-based classification |
| sites are an increasingly popular way to | | | | of Internet resources (such as web sites) is |
| locate, classify, rank, and share Internet | | | | done by human beings, who understand the |
| resources through the practice of tagging and | | | | content of the resource, as opposed to |
| inferences drawn from grouping and analysis | | | | software which algorithmically attempts to |
| of tags. | | | | determine the meaning of a resource. This |
| | | | provides for semantically classified tags, |
| History | | | | which are hard to find with contemporary |
| | | | search engines. |
| The concept of shared online bookmarking | | | | |
| dates back to April 1996 with the launch of | | | | Additionally, as people bookmark resources |
| Within the next three years online bookmark | | | | that they find useful, resources that are of |
| services became competitive, with | | | | more use are bookmarked by more users. Thus, |
| venture-backed companies like Backflip, | | | | such a system will "rank" a resource based on |
| Blink, Clip2, Hotlinks, Quiver, and others | | | | its perceived utility. This is arguably a |
| entering the market. Lacking viable models | | | | more useful metric for end users than other |
| for making money, most of this early | | | | systems which rank resources based on the |
| generation of social bookmarking companies | | | | number of external links pointing to it. |
| failed as the dot-com bubble burst. The | | | | |
| contemporary concepts of social bookmarking | | | | Automatic Notification |
| and tagging took root with the launch of the | | | | |
| web site oneview in 1999[1] and del.icio.us, | | | | Since the classification and ranking of |
| in September of 2003. | | | | resources is a continuously evolving process, |
| | | | many social bookmarking services allow users |
| Functional Overview | | | | to subscribe to syndication feeds (see RSS) |
| | | | based on tags, or collection of tag terms. |
| In a social bookmarking system, users store | | | | This allows subscribers to become aware of |
| lists of Internet resources, which they find | | | | new resources for a given topic, as they are |
| useful. Often, these lists are publicly | | | | noted, tagged, and classified by other users. |
| accessible, and other people with similar | | | | |
| interests can view the links by category, | | | | Disadvantages |
| tags, or even randomly. Some social | | | | |
| bookmarking systems allow for privacy on a | | | | There are drawbacks to such tag-based systems |
| per-bookmark basis. | | | | as well: no standard set of keywords (also |
| | | | known as controlled vocabulary), no standard |
| They also categorize their resources by the | | | | for the structure of such tags (e.g. singular |
| use of informally assigned, user-defined | | | | vs. plural, capitalization, etc.), mistagging |
| keywords or tags (see folksonomy). Most | | | | due to spelling errors, tags that can have |
| social bookmarking services allow users to | | | | more than one meaning, unclear tags due to |
| search for bookmarks which are associated | | | | synonym/antonym confusion, highly unorthodox |
| with given "tags", and rank the resources by | | | | and "personalized" tag schemas from some |
| the number of users which have bookmarked | | | | users, and no mechanism for users to indicate |
| them. Many social bookmarking services also | | | | hierarchical relationships between tags (e.g. |
| have implemented algorithms to draw | | | | a site might be labeled as both cheese and |
| inferences from the tag keywords that are | | | | cheddar, with no mechanism that might |
| assigned to resources by examining the | | | | indicate that cheddar is a refinement or |
| clustering of particular keywords, and the | | | | sub-class of cheese). |
| relation of keywords to one another. | | | | |
| | | | The separate (but related) tagging and social |
| Advantages | | | | bookmarking services are, however, evolving |
| | | | rapidly, and these shortcomings could |
| This system has several advantages over | | | | possibly be addressed in the near future. |
| traditional automated resource location and | | | | |