By: shahid Iqbal

Tags are simple pieces of data (usually no more than 1-3 words) that describe the item tagged

Tags provide information about the item as well as make it easier to see related Item

Tag is a word or term linked to another piece of data as metadata.

Use for Labeling digital content,such as photo,video clip and bookmark.

Tags are not keywords. they aren't the same as keywords written in a <meta/> tag.

Tags are exposed to the reader - they are visible and often can be manipulated by the reader.

Meta tags are written only by the author of the document and can't be modified.

Tags are popular as social networking tools. You’ll see tags in use at Flicker Del.icio.us , lastfm and other places.

Readers assign their own tags to content.

In tagging system, there is no explicit information about the meaning or semantic of each tag.

User can apply new tags to an item as easily as applying older tags.

Tagging allows users to classify their collections of items in the ways that they find useful,

When users can freely choose tags, , the resulting metadata can include homonyms (the same tags used with different meanings) and synonyms (multiple tags for the same concept), which may lead to inappropriate connections between items and inefficient searches for information about a subject.

For example, the tag "orange" may refer to the fruit or the color, and items related to a version of Apple's operating system

Tag is a word or term linked to another piece of data as metadata.

To define or characterize data from the user perspective who adds the tags.

Tag clouds are visual representations of social tags, ◦ Displayed in paragraph-style layout,◦ Usually in alphabetical order ◦ Similar to a tag cloud ◦ Relative size , weight and color of the font for the tag

corresponds to the relative frequency of its use◦ More popular tags are presented in a larger font

and/or a different color.

By default the cloud automatically excludes a large number of common "noise" words, like ◦ Such as "a", "and", "the" and so forth.◦ A limit may be set on the number of keywords

included in the result set.◦ To make the cloud easier to read and present.

Tag clouds can also act as navigational devices • Each keyword displayed in the cloud is a live link • User can click the link to navigate to the "detail"

web pages,

Tag clouds have several drawbacks from a perceptual perspective. .• Difficult to compare all of the tags with a similar

size.• Visual comparisons difficult in data analysis.• Length of the word is conflicted with its size• Another problem in tag cloud layout is that items

with similar meaning cause confusion.

Tag maps are tag clouds in which the position of words is based upon real geographical space and sizes represent word importance at specific locations

The prominence of tags for inclusion in a tag cloud is computed as the number of times the tag is used for tagging.

Tag maps, prominence is necessarily constrained by space

i.e. the number of times a tag or word is used within a localized area

It is a classification scheme that uses a crowd rather than experts to parse content.

Word folksonomy is a combination of folks, meaning "people", and -onomy, meaning "management".

Mean “management by people” Folksonomy method of collaboratively creating

and managing tags to annotate and categorize content.

A visual representation of a folksonomy is the tag cloud

TagCrowd is a web application for visualizing word frequencies in any user-supplied text

A website that Take Text file or Website URL to generate Tag cloud

•Y-axis shows Tag weights for that URL.

Del.icio.us is a social bookmarking web site that allows users to store, label, and categorize their online bookmarks in public view.

del.icio.us (http://del.icio.us), Digg (http://digg.net) for bookmarks Flickr (http://flickr.com) for photos. Weblog authors usually tag their articles

and specialized search engines like Technorati (http://technorati.com/)

BibSonomy (http://bibsonomy.org, Connotea (http://connotea.org, CiteULike (http://citeulike.org/), LibraryThing (http://librarything.com)

References1.Tag Clouds: Data Analysis Tool or

Social Signaller?2.Scriptcloud.com: Content Clouds for

Screenplays Stewart McKie Dept. of Media Arts, Royal Holloway

3.Cloudalicious: Folksonomy Over Time4.A Quantitative Analysis of Collaborative

Tags: Evaluation for Information Retrieval—a Preliminary Study

5.Google.com