Web directory
Encyclopedia
A web directory or link directory is a directory
on the World Wide Web
. It specializes in linking
to other web sites and categorizing
those links.
A web directory is not a search engine
and does not display lists of web pages based on keyword
s; instead, it lists web sites by category and subcategory. Most web directory entries are also not found by web crawlers
but by humans. The categorization is usually based on the whole web site rather than one page or a set of keywords, and sites are often limited to inclusion in only a few categories. Web directories often allow site owners to submit their site for inclusion, and have editors review submissions for fitness.
RSS directories are similar to web directories, but contain collections of RSS feeds, instead of links to web sites.
. Shopping directories specialize in the listing of retail e-commerce sites.
Examples of well known general web directories are Yahoo! Directory
and the Open Directory Project
(ODP). ODP is significant due to its extensive categorization and large number of listings and its free availability
for use by other directories and search engines.
However, a debate over the quality of directories and databases still continues, as search engines use ODP's content without real integration, and some experiment using clustering
. There have been many attempts to make directory development easier, such as using automated submission of related links by script, or any number of available PHP
portals and programs. Recently, social software
techniques have spawned new efforts of categorization, with Amazon.com
adding tagging
to their product pages.
Directories have various features in listing, often depend upon the price paid for inclusion:
Human-edited directories are often targeted by SEOs
on the basis that links from reputable sources will improve rankings in the major search engine
s. Some directories may prevent search engines from rating a displayed link by using redirects, nofollow
attributes, or other techniques.
Many human-edited directories, including the Open Directory Project
, Salehoo
and World Wide Web Virtual Library
, are edited by volunteers, who are often experts in particular categories. These directories are sometimes criticized due to long delays in approving submissions, or for rigid organizational structures and disputes among volunteer editors.
In response to these criticisms, some volunteer-edited directories have adopted wiki
technology, to allow broader community participation in editing the directory (at the risk of introducing lower-quality, less objective entries).
Another direction taken by some web directories is the paid for inclusion model. This method enables the directory to offer timely inclusion for submissions and generally fewer listings as a result of the paid model. They often offer additional listing options to further enhance listings, including features listings and additional links to inner pages of the listed web site. These options typically have an additional fee associated, but offer significant help and visibility to sites and/or their inside pages.
Today submission of websites to web directories is considered a common SEO (search engine optimization) technique to get back-links for the submitted web site. One distinctive feature of 'directory submission' is that it cannot be fully automated like search engine submissions. Manual directory submission is a tedious and time consuming job and is often outsourced by the webmasters.
Directory (databases)
Generally, a directory, as used in computing and telephony, refers to a repository or database of information which is heavily optimized for reading, under the assumption that data updates are very rare compared to data reads...
on the World Wide Web
World Wide Web
The World Wide Web is a system of interlinked hypertext documents accessed via the Internet...
. It specializes in linking
Hyperlink
In computing, a hyperlink is a reference to data that the reader can directly follow, or that is followed automatically. A hyperlink points to a whole document or to a specific element within a document. Hypertext is text with hyperlinks...
to other web sites and categorizing
Categorization
Categorization is the process in which ideas and objects are recognized, differentiated and understood. Categorization implies that objects are grouped into categories, usually for some specific purpose. Ideally, a category illuminates a relationship between the subjects and objects of knowledge...
those links.
A web directory is not a search engine
Web search engine
A web search engine is designed to search for information on the World Wide Web and FTP servers. The search results are generally presented in a list of results often referred to as SERPS, or "search engine results pages". The information may consist of web pages, images, information and other...
and does not display lists of web pages based on keyword
Keyword (Internet search)
An index term, subject term, subject heading, or descriptor, in information retrieval, is a term that captures the essence of the topic of a document. Index terms make up a controlled vocabulary for use in bibliographic records. They are an integral part of bibliographic control, which is the...
s; instead, it lists web sites by category and subcategory. Most web directory entries are also not found by web crawlers
Web crawler
A Web crawler is a computer program that browses the World Wide Web in a methodical, automated manner or in an orderly fashion. Other terms for Web crawlers are ants, automatic indexers, bots, Web spiders, Web robots, or—especially in the FOAF community—Web scutters.This process is called Web...
but by humans. The categorization is usually based on the whole web site rather than one page or a set of keywords, and sites are often limited to inclusion in only a few categories. Web directories often allow site owners to submit their site for inclusion, and have editors review submissions for fitness.
RSS directories are similar to web directories, but contain collections of RSS feeds, instead of links to web sites.
Scope of listing
Most of the directories are general in scope and list websites across a wide range of categories, regions and languages. But some niche directories focus on restricted regions, single languages, or specialist sectors. One type of niche directory with a large number of sites in existence is the shopping directoryShopping directory
A shopping directory is a "Yellow Pages Directory Style" website similar to the Open Directory Project or the Yahoo! Directory with focus on sites that sell products or services, usually referred to as ecommerce websites....
. Shopping directories specialize in the listing of retail e-commerce sites.
Examples of well known general web directories are Yahoo! Directory
Yahoo! Directory
The Yahoo! Directory is a web directory that rivals the Open Directory Project in size. The directory was Yahoo!'s first offering. When Yahoo! changed to crawler-based listings for its main results in October 2002, the human-edited directory's significance dropped, but it was still being updated in...
and the Open Directory Project
Open Directory Project
The Open Directory Project , also known as Dmoz , is a multilingual open content directory of World Wide Web links. It is owned by Netscape but it is constructed and maintained by a community of volunteer editors.ODP uses a hierarchical ontology scheme for organizing site listings...
(ODP). ODP is significant due to its extensive categorization and large number of listings and its free availability
Open content
Open content or OpenContent is a neologism coined by David Wiley in 1998 which describes a creative work that others can copy or modify. The term evokes open source, which is a related concept in software....
for use by other directories and search engines.
However, a debate over the quality of directories and databases still continues, as search engines use ODP's content without real integration, and some experiment using clustering
Data clustering
Cluster analysis or clustering is the task of assigning a set of objects into groups so that the objects in the same cluster are more similar to each other than to those in other clusters....
. There have been many attempts to make directory development easier, such as using automated submission of related links by script, or any number of available PHP
PHP
PHP is a general-purpose server-side scripting language originally designed for web development to produce dynamic web pages. For this purpose, PHP code is embedded into the HTML source document and interpreted by a web server with a PHP processor module, which generates the web page document...
portals and programs. Recently, social software
Social software
Social software applications include communication tools and interactive tools. Communication tools typically handle the capturing, storing and presentation of communication, usually written but increasingly including audio and video as well. Interactive tools handle mediated interactions between a...
techniques have spawned new efforts of categorization, with Amazon.com
Amazon.com
Amazon.com, Inc. is a multinational electronic commerce company headquartered in Seattle, Washington, United States. It is the world's largest online retailer. Amazon has separate websites for the following countries: United States, Canada, United Kingdom, Germany, France, Italy, Spain, Japan, and...
adding tagging
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...
to their product pages.
Directories have various features in listing, often depend upon the price paid for inclusion:
- Free submission – there is no charge for the review and listing of the site
- Reciprocal link – a link back to the directory must be added somewhere on the submitted site in order to get listed in the directory
- No Reciprocal link — a web directory where you will submit your links for free and no need to add link back to your website.
- Paid submission – a one-time or recurring fee is charged for reviewing/listing the submitted link
- No follow – there is a
rel="nofollow"attribute associated with the link, meaning search engines will give no weight to the link. - Featured listing – the link is given a premium position in a category (or multiple categories) or other sections of the directory, such as the homepage. Sometimes called sponsored listing.
- Bid for position – where sites are ordered based on bids
- Affiliate linksAffiliate marketingAffiliate marketing is a marketing practice in which a business rewards one or more affiliates for each visitor or customer brought about by the affiliate's own marketing efforts...
– where the directory earns commission for referred customers from the listed websites
Human-edited directories
A human-edited directory is created and maintained by editors who add links based on the policies particular to that directory.Human-edited directories are often targeted by SEOs
Search engine optimization
Search engine optimization is the process of improving the visibility of a website or a web page in search engines via the "natural" or un-paid search results...
on the basis that links from reputable sources will improve rankings in the major search engine
Web search engine
A web search engine is designed to search for information on the World Wide Web and FTP servers. The search results are generally presented in a list of results often referred to as SERPS, or "search engine results pages". The information may consist of web pages, images, information and other...
s. Some directories may prevent search engines from rating a displayed link by using redirects, nofollow
Nofollow
nofollow is a value that can be assigned to the rel attribute of an HTML a element to instruct some search engines that a hyperlink should not influence the link target's ranking in the search engine's index...
attributes, or other techniques.
Many human-edited directories, including the Open Directory Project
Open Directory Project
The Open Directory Project , also known as Dmoz , is a multilingual open content directory of World Wide Web links. It is owned by Netscape but it is constructed and maintained by a community of volunteer editors.ODP uses a hierarchical ontology scheme for organizing site listings...
, Salehoo
Salehoo
SaleHoo Group Limited is a New Zealand based e-commerce company that manages SaleHoo.com, a website specializing in global trading between wholesalers and retailers...
and World Wide Web Virtual Library
World Wide Web Virtual Library
The World Wide Web Virtual Library was the first index of content on the World Wide Web and still operates as a directory of e-texts and information sources on the web. It was started by Tim Berners-Lee, the creator of HTML and the World Wide Web itself, in 1991 at CERN in Geneva...
, are edited by volunteers, who are often experts in particular categories. These directories are sometimes criticized due to long delays in approving submissions, or for rigid organizational structures and disputes among volunteer editors.
In response to these criticisms, some volunteer-edited directories have adopted wiki
Wiki
A wiki is a website that allows the creation and editing of any number of interlinked web pages via a web browser using a simplified markup language or a WYSIWYG text editor. Wikis are typically powered by wiki software and are often used collaboratively by multiple users. Examples include...
technology, to allow broader community participation in editing the directory (at the risk of introducing lower-quality, less objective entries).
Another direction taken by some web directories is the paid for inclusion model. This method enables the directory to offer timely inclusion for submissions and generally fewer listings as a result of the paid model. They often offer additional listing options to further enhance listings, including features listings and additional links to inner pages of the listed web site. These options typically have an additional fee associated, but offer significant help and visibility to sites and/or their inside pages.
Today submission of websites to web directories is considered a common SEO (search engine optimization) technique to get back-links for the submitted web site. One distinctive feature of 'directory submission' is that it cannot be fully automated like search engine submissions. Manual directory submission is a tedious and time consuming job and is often outsourced by the webmasters.