Exploring the World of Vertical Search

by Joe Dolson (March 3, 2006)

If you like this article, you may be also interested in Search Engine Relationships, a quick guide to understanding the interactions between search engines.

What IS a vertical search engine?

One of the great debates in vertical search argues the definition of "vertical search engine." I will address this in some detail, as the distinction is highly significant from a search engine marketing point of view. To state it very briefly, not all vertical search engines are web search engines. The first key is in the definition of a search engine. Literally speaking, I would define a search engine as a means to locate information contained within a defined information source.

In the case of major web search engines, like Google or Yahoo, that information source is the entire World Wide Web. But the World Wide Web is not the only thing worth searching! Your operating system is outfitted with a local search engine for your computer files and many web sites have search tools for just their own resources. But when we discuss search engine marketing, we're not discussing how to give your website more prominence within some site's internal search results!

The question comes down to data sources - vertical search simply means search defined around a core topic, industry, or information related by some common factor. Your site search, arguably, is a vertical search defined around your website.

So what you need to know is which so-called "vertical search engines" are search tools using their own proprietary information and which are actually drawing information from publicly available web resources. If a tool uses specific collections of databases, such as Kayak, it is no more a web search engine than this site.

What are some examples of "real" vertical search engines? Any application which draws information from the general resources of the web is an actual vertical search engine, as we have defined the term. Technorati aggregates information from blogs and provides the ability to search all blogs. Scirus searches the web and online journals for scientific information. A more extensive (though still very much partial) list of other vertical search engines is provided at the end of this article.

Advantages and Disadvantages?

The main advantage to vertical search is that you can effectively reduce the number of undesirable results in your search. If you're looking for an audio file, there's no reason to use Google - a general search engine is likely to bring up a large number of irrelevant results. Naturally, there are a lot of advanced options available with the major search engines to help refine your search. Most general-purpose search tools have created "sub-search" options to create vertical search options within their indices. Google's well-known offerings Google News and Google Images are just two of the better known examples.

For search engine marketing, the advantage to vertical search is that advertisers can easily target a search engine which is specialized to their industry. Of course, not every industry is large enough for a truly significant vertical search engine - but if you're in certain industries with broad scope, like travel, retail, or multimedia, you have an excellent chance of building an effective strategy through these search engines. Although the viewer traffic may be less than what you'd get on Google or Yahoo, the audience can be much more targeted.

But it's debatable how effective these new tools will actually be at attracting users. As the major search engines get more and more sophisticated in understanding your search, these specialized searches seem like they may become less important. Many of the top search engines have begun to automatically incorporate a type of "vertical search" into their standard searches! This technique, sometimes referred to as vertical creep involves the incorporation of results from alternate indices when the search engine thinks those results may be more relevant. For example, using Google, I performed a search on "U2" which brought results from Google's music search index at the top.

An additional possible flaw from vertical search is a decreased ability to bring you unexpected finds. It sometimes happens when searching that you'll discover something very interesting simply because it contained the keywords you were looking for - despite being generally unrelated. To search engine marketing, certainly not a great concern - except to the degree that this is something which appeals to the searcher. These results add an unpredictable "flare" to search which may (this is entirely hypothetical) keep a user attached to full-scale search engines.

This sophistication from the major players in search may serve to crush the hopes of at least some vertical search tools. I think that vertical search tools in certain areas are bound to succeed - particularly content search tools such as Technorati or multimedia tools like Truveo. The core of a vertical search tool is in adding value by decreasing results. The goal is obviously to remove anything irrelevant in order to streamline your searching. Convincing the marketplace that your service is superior because it provides less may be a challenge for vertical search engines.

Suggested other reading:

Partial List of Vertical Search Engines

Technology and Science

Blogs and News

Multimedia

Classifieds or "Other"

Creative Commons License This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivs2.5 License.

Joe Dolson is a web designer and programmer specializing in accessible web design. He's worked as a freelance consultant and designed since the beginning of 2005 and has written extensively at his private business website for accessible web design and in the InterDigital Strategies blog. His main web interests are in accessibility, useability, and ethics.