A trackback allows one website to notify another about an update. It is one of four types of linkback methods for

website A website (also written as a web site) is any web page whose content is identified by a common domain name and is published on at least one web server. Websites are typically dedicated to a particular topic or purpose, such as news, educatio ...

authors to request notification when somebody links to one of their documents. This enables authors to keep track of who is linking to their articles. Some

weblog A blog (a Clipping (morphology), truncation of "weblog") is an informational website consisting of discrete, often informal diary-style text entries also known as posts. Posts are typically displayed in Reverse chronology, reverse chronologic ...

software, such as SilverStripe,

WordPress WordPress (WP, or WordPress.org) is a web content management system. It was originally created as a tool to publish blogs but has evolved to support publishing other web content, including more traditional websites, electronic mailing list, ma ...

Drupal Drupal () is a free and open-source web content management system (CMS) written in PHP and distributed under the GNU General Public License. Drupal provides an open-source back-end framework for at least 14% of the top 10,000 websites worldwide ...

, and

Movable Type Movable type (US English; moveable type in British English) is the system and technology of printing and typography that uses movable Sort (typesetting), components to reproduce the elements of a document (usually individual alphanumeric charac ...

, supports automatic pingbacks where all the links in a published article can be pinged when the article is published. The term is used colloquially for any kind of linkback.

History

The TrackBack specification was created by

Six Apart Six Apart Ltd., sometimes abbreviated 6A, is a software company known for creating the Movable Type blogware, TypePad blog hosting service, and Vox (the blogging platform). The company also is the former owner of LiveJournal. Six Apart is ...

, which first implemented it in its

blogging software in August 2002. The TrackBack has since been implemented in most other blogging tools. Six Apart started a working group in February 2006 to improve the Trackback protocol with the goal to eventually have it approved as an Internet standard by the

IETF The Internet Engineering Task Force (IETF) is a standards organization for the Internet standard, Internet and is responsible for the technical standards that make up the Internet protocol suite (TCP/IP). It has no formal membership roster ...

. One notable blogging service that does not support trackback is

Blogger A blog (a Clipping (morphology), truncation of "weblog") is an informational website consisting of discrete, often informal diary-style text entries also known as posts. Posts are typically displayed in Reverse chronology, reverse chronologic ...

. Instead, Blogger provides "backlinks", which allow users to employ Google's search infrastructure to show links between blog entries.

Function

A trackback is an acknowledgment. This acknowledgment is sent via a network signal (

XML-RPC XML-RPC is a remote procedure call (RPC) protocol which uses XML to encode its calls and HTTP as a transport mechanism.Simon St. Laurent, Joe Johnston, Edd Dumbill. (June 2001) ''Programming Web Services with XML-RPC.'' O'Reilly. First Edition. ...

ping) from the originating site to the receiving site. The receptor often publishes a link back to the originator indicating its worthiness. Trackback requires both sites to be trackback-enabled in order to establish this communication. Trackbacks are used primarily to facilitate communication between

blog A blog (a Clipping (morphology), truncation of "weblog") is an informational website consisting of discrete, often informal diary-style text entries also known as posts. Posts are typically displayed in Reverse chronology, reverse chronologic ...

s; if a blogger writes a new entry commenting on, or referring to, an entry found at another blog, and both blogging tools support the TrackBack protocol, then the commenting blogger can notify the other blog with a "TrackBack ping"; the receiving blog will typically display summaries of, and links to, all the commenting entries below the original entry. This allows for conversations spanning several blogs that readers can easily follow.

Software support

Blogging software that supports the TrackBack protocol displays a "TrackBack

URL A uniform resource locator (URL), colloquially known as an address on the Web, is a reference to a resource that specifies its location on a computer network and a mechanism for retrieving it. A URL is a specific type of Uniform Resource Identi ...

" with every entry. This URL is used by the commenting blogger, whose software will send

XML Extensible Markup Language (XML) is a markup language and file format for storing, transmitting, and reconstructing data. It defines a set of rules for encoding electronic document, documents in a format that is both human-readable and Machine-r ...

-formatted information about the new entry to this URL. Some blogging tools are able to discover these TrackBack URLs automatically, others require the commenting blogger to enter them manually.

Spam

Some individuals or companies have abused the TrackBack feature to insert spam links on some blogs. This is similar to comment spam but avoids some of the safeguards designed to stop the latter practice. As a result, TrackBack

spam filter Email filtering is the processing of email to organize it according to specified criteria. The term can apply to the intervention of human intelligence, but most often refers to the automatic processing of messages at an SMTP server, possibly ap ...

s similar to those implemented against comment spam now exist in many weblog publishing systems. Many blogs have stopped using trackbacks because dealing with spam became too much of a burden.

References

External links