Aggregator
Encyclopedia
In computing, a feed aggregator, also known as a feed reader, news reader, RSS
RSS
-Mathematics:* Root-sum-square, the square root of the sum of the squares of the elements of a data set* Residual sum of squares in statistics-Technology:* RSS , "Really Simple Syndication" or "Rich Site Summary", a family of web feed formats...

 reader
or simply aggregator, is client software
Client (computing)
A client is an application or system that accesses a service made available by a server. The server is often on another computer system, in which case the client accesses the service by way of a network....

 or a Web application
Web application
A web application is an application that is accessed over a network such as the Internet or an intranet. The term may also mean a computer software application that is coded in a browser-supported language and reliant on a common web browser to render the application executable.Web applications are...

 which aggregates syndicated web content
Web syndication
Web syndication is a form of syndication in which website material is made available to multiple other sites. Most commonly, web syndication refers to making web feeds available from a site in order to provide other people with a summary or update of the website's recently added content...

 such as news headlines, blogs, podcasts
Podcasting
A podcast is a series of digital media files that are released episodically and often downloaded through web syndication...

, and vlog
Vlog
Video blogging, sometimes shortened to vlogging or vidding or vidblogging is a form of blogging for which the medium is video, and is a form of Web television. Entries often combine embedded video or a video link with supporting text, images, and other metadata. Entries can be recorded in one take...

s in a single location for easy viewing.

News aggregation websites

Examples of this sort of website are the Drudge Report
Drudge Report
The Drudge Report is a news aggregation website. Run by Matt Drudge with the help of Joseph Curl and Charles Hurt, the site consists mainly of links to stories from the United States and international mainstream media about politics, entertainment, and current events as well as links to many...

 and the Huffington Post. There are also websites like Google News
Google News
Google News is a free news aggregator provided by Google Inc, selecting recent items from thousands of publications by an automatic aggregation algorithm....

, where aggregation is entirely automatic, using algorithms which carry out contextual analysis and group similar stories together.

News aggregation websites started with sites like the Drudge Report, NewsNow, Andrew Breitbart and the Huffington Post, where content was still entered by humans. Newer sites such as Google News on the other hand are based on algorithms filling the content from a range of either automatically selected or manually added sources.

Functions

Aggregators reduce the time and effort needed to regularly check websites for updates, creating a unique information space or "personal newspaper". Once subscribed to a feed, an aggregator is able to check for new content at user-determined intervals and retrieve the update. The content is sometimes described as being "pulled
Pull technology
Pull technology or client pull is a style of network communication where the initial request for data originates from the client, and then is responded to by the server. The reverse is known as push technology, where the server pushes data to clients.. Usually, customers will look for a site and...

" to the subscriber, as opposed to "pushed
Push technology
Push technology, or server push, describes a style of Internet-based communication where the request for a given transaction is initiated by the publisher or central server...

" with email or IM. Unlike recipients of some "pushed" information, the aggregator user can easily unsubscribe from a feed.

Aggregator features are frequently built into portal sites, Web browsers, and email programs.

The aggregator provides a consolidated view of the content in a single browser display or desktop application. Aggregators with podcasting capabilities can automatically download media files, such as MP3
MP3
MPEG-1 or MPEG-2 Audio Layer III, more commonly referred to as MP3, is a patented digital audio encoding format using a form of lossy data compression...

 recordings. In some cases, these can be automatically loaded onto portable media player
Portable media player
A portable media player or digital audio player, is a consumer electronics device that is capable of storing and playing digital media such as audio, images, video, documents, etc. the data is typically stored on a hard drive, microdrive, or flash memory. In contrast, analog portable audio...

s (like iPod
IPod
iPod is a line of portable media players created and marketed by Apple Inc. The product line-up currently consists of the hard drive-based iPod Classic, the touchscreen iPod Touch, the compact iPod Nano, and the ultra-compact iPod Shuffle...

s) when they are connected to the end-user's computer.

Recently, so-called RSS-narrators have appeared, which not only aggregate text-only news feeds, but also convert them into audio recordings for offline listening.

The syndicated content an aggregator will retrieve and interpret is usually supplied in the form of RSS
RSS (file format)
RSS is a family of web feed formats used to publish frequently updated works—such as blog entries, news headlines, audio, and video—in a standardized format...

 or other XML
XML
Extensible Markup Language is a set of rules for encoding documents in machine-readable form. It is defined in the XML 1.0 Specification produced by the W3C, and several other related specifications, all gratis open standards....

-formatted data, such as RDF
Resource Description Framework
The Resource Description Framework is a family of World Wide Web Consortium specifications originally designed as a metadata data model...

/XML or Atom
Atom (standard)
The name Atom applies to a pair of related standards. The Atom Syndication Format is an XML language used for web feeds, while the Atom Publishing Protocol is a simple HTTP-based protocol for creating and updating web resources.Web feeds allow software programs to check for updates published on a...

.

For example, if there are many sites you visit frequently, without RSS the only way you can find out if anything on the sites has been updated is to go to each site individually. This can take a long time. Aggregation technology helps you to integrate these websites in one browser or page that can show the new or updated information from all the sites you choose, regardless of whether the content is text, music, pictures, or video.
Customers only need to find an RSS feed on the Internet and add that in their RSS reader. There are many successful on-line RSS Readers, such as My Yahoo! and Google Reader
Google Reader
Google Reader is a Web-based aggregator, capable of reading Atom and RSS feeds online or offline. It was released by Google on October 7, 2005 through Google Labs. Reader was graduated from beta status on September 17, 2007.-Interface:...

. There is also a variety of RSS software: Feed Demon, and RSS Reader for example.
For network security, users can choose what items can be shown in their RSS readers, like title, author or others, so it can exclude spam.

Varieties

The variety of software applications and components that are available to collect, format, translate, and republish XML feeds is a testament to the flexibility of the format and has shown the usefulness of presentation-independent data
Separation of presentation and content
Separation of presentation and content is a common idiom, a design philosophy, and a methodology applied in the context of various publishing technology disciplines, including information retrieval, template processing, web design, web development, word processing, desktop publishing,...

.

Web-based

The most commonly known web-based aggregators are reader applications on the web. These are meant for personal use and are hosted on remote servers. Because the application is available via the Web, it can be accessed anywhere by a user with an Internet connection.

More advanced methods of aggregating feeds are provided via Ajax
Ajax (programming)
Ajax is a group of interrelated web development methods used on the client-side to create asynchronous web applications...

 coding techniques and XML components known as Web widget
Web widget
In computing a web widget is a software widget for the web. It's a small application that can be installed and executed within a web page by an end user. They are derived from the idea of code reuse. Other terms used to describe web widgets include: portlet, gadget, badge, module, webjit, capsule,...

s. Ranging from full-fledged applications to small fragments of code that can be integrated into larger programs, they allow users to aggregate OPML
OPML
OPML is an XML format for outlines...

 files, email services, documents, or feeds into a single interface. Many customizable homepage and portal implementations provide such functionality.

In addition to aggregator services mainly for individual use, there are web applications that can be used to aggregate several blogs into one. One such variety—called planet sites—are used by online communities to aggregate community blogs in a centralized location. They are named after the Planet aggregator
Planet aggregator
In online media, Planet is a feed aggregator application designed to collect posts from the weblogs of members of an Internet community and display them on a single page. Planet runs on a web server. It creates pages with entries from the original feeds in chronological order, most recent entries...

, a server application designed for this purpose.

Client software

Client software aggregators are installed applications designed to collect Web feed subscriptions and group them together using a user-friendly interface. The graphical user interface of such applications often closely resembles that of popular e-mail client
E-mail client
An email client, email reader, or more formally mail user agent , is a computer program used to manage a user's email.The term can refer to any system capable of accessing the user's email mailbox, regardless of it being a mail user agent, a relaying server, or a human typing on a terminal...

s, using a three-panel composition in which subscriptions are grouped in a frame on the left, and individual entries are browsed, selected, and read in frames on the right.

Software aggregators can also take the form of news ticker
News ticker
A news ticker resides in the lower third of the television screen space on television news networks dedicated to presenting headlines or minor pieces of news. It may also refer to a long, thin scoreboard-style display seen around the front of some offices or public buildings...

s which scroll feeds like ticker tape
Ticker tape
Ticker tape was the earliest digital electronic communications medium, transmitting stock price information over telegraph lines, in use between around 1870 through 1970...

, alerters that display updates in windows as they are refreshed, web browser macro tools or as smaller components (sometimes called plugins or extension
Extension (computing)
Software extension, is a file containing programming that serves to extend the capabilities of or data available to a more basic program. It is a kind of list of commands which are directly included in the program. This term often coincides with the plug-in...

s), which can integrate feeds into the operating system
Operating system
An operating system is a set of programs that manage computer hardware resources and provide common services for application software. The operating system is the most important type of system software in a computer system...

 or software applications such as a Web browser.

Media aggregators

Media aggregators are sometimes referred to as "Podcatchers" due to the popularity of the term "podcast
Podcast
A podcast is a series of digital media files that are released episodically and often downloaded through web syndication...

" used to refer to a web feed containing audio or video. Media aggregators refer to applications, client software or Web based, which maintain subscriptions to feeds that contain audio or video media enclosures. They can be used to automatically download media, playback the media within the application interface, or synchronize media content with a portable media player.

Broadcatching

Several BitTorrent client software applications have added the ability to "broadcatch"
Broadcatching
Broadcatching is the downloading of digital content that has been made available over the Internet using RSS.The general idea is to use an automated mechanism to aggregate various web feeds and download content for viewing or presentation purposes....

 torrents of distributed multimedia through the aggregation of web feeds.

Feed filtering

One of the problems with news aggregators is that the volume of articles can sometimes be overwhelming, especially when the user has many Web feed subscriptions. As a solution, many feed readers allow users to tag
Tag (metadata)
In online computer systems terminology, a tag is a non-hierarchical keyword or term assigned to a piece of information . This kind of metadata helps describe an item and allows it to be found again by browsing or searching...

 each feed with one or more keywords which can be used to sort and filter the available articles into easily navigable categories. Another option is to import the user's Attention Profile
APML
APML is an XML-based format for expressing a person's interests and dislikes.-Overview:APML allows people to share their own personal attention profile in much the same way that OPML allows the exchange of reading lists between news readers...

 to filter items based on their relevance to the user's interests.

See also

  • Comparison of feed aggregators
    Comparison of feed aggregators
    The following is a comparison of notable RSS feed aggregators. Often e-mail programs and web browsers have the ability to display RSS feeds. They are listed here, too.Many BitTorrent clients support RSS feeds for broadcatching ....

  • Web feed
    Web feed
    A web feed is a data format used for providing users with frequently updated content. Content distributors syndicate a web feed, thereby allowing users to subscribe to it. Making a collection of web feeds accessible in one spot is known as aggregation, which is performed by an aggregator...

  • Metasearch engine
    Metasearch engine
    A metasearch engine is a search tool that sends user requests to several other search engines and/or databases and aggregates the results into a single list or displays them according to their source. Metasearch engines enable users to enter search criteria once and access several search engines...

  • Lifestreaming
    Lifestreaming
    The term lifestream was coined by Eric Freeman and David Gelernter at Yale University in the mid-1990s to describe "...a time-ordered stream of documents that functions as a diary of your electronic life; every document you create and every document other people send you is stored in your lifestream...


External links

The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
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