In computers, a machine tag is also called a triple tag. Web developers and software programmers sometimes use triple tags to give their users more precision in tagging and searching. Using a machine tag gives more power to the user in terms of retrieving items, especially if said items do not contain the tag data itself such as in photos and images. The machine tag may also be useful in the emerging tagging practice called geotagging. Geotagging is the method used for putting geographical identification, such as latitude and altitude, on photographs, websites, or videos.
Several websites help site visitors navigate their pages by letting users tag their content. Some websites implement the use of a machine tag to allow their users to have more precision in tagging. A machine tag uses a special syntax to provide more information about an existing tag. The syntax of a machine tag involves a value, a predicate, and a namespace. A namespace describes in which classification a tag is included, the predicate describes the property of the namespace, while the value contains any characters usually wrapped in quotes.
The term tag in computer systems and Internet terminology refers to a keyword attached or assigned to a group of data or related pieces of information. It can be used on blocks of text, digital images, Internet bookmarks, and computer files. Tags are descriptive of items that may or may not be visible to users. In this way, tags are considered as metadata. They are something that is not necessary to be viewable by people browsing websites or people using computer files, but are extremely helpful to machines and search engines.
Tagging items with a tag makes them easier to find when people search for them using search engines or embedded search features in websites or operating systems. Browsing for a particular item can also be made easier by having tag clouds on web pages. Tag clouds provide a visual means for users to see which terms are most popular and which terms are not usually searched for by users. A tag is usually chosen in an informal manner by the people uploading or publishing information.
Other websites use other forms of tagging that cater to their visitors' specialized and unique needs. Websites that use geotagging such as Flickr use machine tags to add geographic location information to photos. Twitter uses hash tags to describe the information contained in a tweet. Hash tags are kept compact to accommodate the character limit of Twitter, which is 140 characters. Whatever form tagging takes, it gives users the flexibility in searching and describing their data for their own convenience and for other people's as well.