Search Engine Essentials


What are Search Engines?

There are numerous different search engines, and all are essentially huge databases containing information about web pages from the internet. A web-based user interface then allows the user to search the contents of this database. The user enters a search-term into the search engine and is presented with a list of web-pages that relate to the search-term. Note that search engine databases have separate records for each web-page, not each website.

Some well known search engines are:

    * Google
    * MSN Search
    * AltaVista
    * Ask Jeeves
    * Hotbot
    * All the Web
    * Yahoo

Although they function in essentially the same way, each search engine varies in the amount and type of information it stores about each web page and the way in which it 'decides' which pages relate to a particular search-term.

How Do Search Engines Work?

Spiders and Robots.

Search Engines gather information about Web Pages using automated software that 'crawls' through the World Wide Web visiting every web-page that it can find. This software is usually referred to as a 'robot' or a 'spider'. When an individual submits a website to a search engine they are requesting that a search engine robot is sent to that page. When a robots visits the page it records not just the URL of the page, but varying amounts of information about the page. The robot then follows every single hyperlink within the page and catalogues those pages, and on it goes following links throughout the internet, cataloguing every page it comes to. Once a web-page has been submitted to a search engine, or has links to it from pages that already get spidered by the search engine robots then there should be no need to re-submit the site to the search engines as the robots will come crawling on a regular basis.

The exact information that robots store within the search engines database is kept a secret so as to prevent 'spamming' of the search engines as much as possible. Despite this, it is fairly easy to decide which elements of the page that the search engines are most likely to record.

SERPS

When a user performs a search within a search engine, the results are presented as a list of web-pages that relate to the search-term. These pages are known as 'Search Engine Results Pages' or SERPS. Search Engines attempt to place the most relevant pages to any given search-term at the top of the SERPS. Therefore, the aim of all Search Engine Optimisation (SEO) techniques is to get a web page as close to the top of these SERPS as possible.

The complex algorithms used to calculate which web pages are most relevant to a given search-term are kept a closely guarded secret by the search engines. Once again this is to prevent spamming of the search engines as it is within the search engines interests to make sure the results presented in the SERPS are as accurate and therefore as useful as possible. Search Engines make money by selling advertising space on their web-pages. Advertisers will only pay to advertise if the pages are viewed by millions of people, and people will only continue to use a search engine if it provides them with useful results. It is therefore important that the pages listed in the SERPS as accurate as possible and not influenced by Search Engine spamming techniques.

Features of some Specific Search Engines.

Search engines have much in common with each other, but each also has its own unique features and peculiarities. It is also worth noting that many search engines share the same database or use the same algorithms, so all are inter-related to varying degrees.

Google

Google is at the moment the most popular and therefore most important of the search engines. It generally provides users with highly relevant SERPS, has a wide coverage and has a clean, easy to use interface. It also offers the ability to search for things other than just web pages, such as images, the contents of newsgroups etc.

From a SEO point of view, Google is incredibly important, but it is also very frustrating. The sandbox effect means that new web pages are often not listed in the Google SERPS for many months after Google first becomes aware of them. This can prove frustrating for webmasters of new websites and makes analysing SEO techniques specifically aimed at Google very difficult in the early months of a websites existence. Google also change the algorithm they use on a regular basis. This process is known as the 'Google Dance' and can result in some unexpected and quite dramatic changes in the ranking of a particular page within the SERPS.

Google also offers paid adverts in addition to its unpaid listings. Some of these adverts are also placed on the pages of its partners. It also provides SERPS for other search engines.

Yahoo

Yahoo used to be a web directory where human editors organised websites into categories. However in 2002 it made a shift to robot-based listings and used Googles database. Then in 2004 Yahoo started using their own database and algorithms. Yahoo has also purchased many other smaller search engines and directories, including some bigger names like Overture (which provides Yahoo's Pay Per Click ads), AltaVista and AllTheWeb. Technology from all of these has been used to build the Yahoo robot.

Ask Jeeves (Ask)

Ask Jeeves was originally marketed as a tool for finding the answers to specific questions on the internet. Because of this users often use it to search for information using whole sentences as questions rather than simple search terms such as 2-3 word phrases as used in most other Search Engines. Other than this it works in much the same way as other Search Engines. It is however fairly popular when users are looking for answers to specific questions and can therefore be an important search engine for websites containing lots of factual information and answers to specific questions. The results actually come from the Teoma Search Engine that it owns.

Teoma

Teoma is a robot-based search engine owned by Ask Jeeves. It has a smaller index of the web than Google. In addition to its SERPS it also provides a "Refine" feature, which offers suggested topics to explore after you do a search. The "Resources" section of results is also unique, pointing users to pages that specifically serve as link resources about various topics.

MSN Search

Although not as popular as Google, this is certainly one to watch. Here in the UK Microsoft are promoting MSN Search heavily with numerous prime-time TV adverts. Microsoft cleary wants a piece of the Search-Engine cake at the expense of Google, and what Microsoft wants in the IT world, it usually gets. MSN Search now has a revamped user interface and a much improved algorithm and is providing very relevant SERPS.

It also seems to react very quickly to changes and new websites get listed very quickly. This means it can be useful for tracking and analysing the effectiveness of SEO and promotion campaigns.

AOL Search

AOL search uses the Google database and is very similar to Google. It is of course used by AOL users, but doesn't have as many features as Google.

Which Search Engines Should I be Concerned about?

From the point of view of a webmaster doing his best to get good organic listings and therefore increase traffic to his website, ALL search engines are important. Every single one is used by real human beings, and any of them are capable of sending the next paying customer to your website. However, due to its popularity Google is at the moment the most important.

Don't however put all your eggs in one basket and aim only to get good listings in Google. Yahoo is also important as its database provides results for a number of other smaller search engines with different user-interfaces. Ask Jeeves may well be important for your content-rich websites due to the nature of the 'complete sentence' search-terms that are often used. And never forget MSN, It is pretty big already and getting bigger all the time. It has the might of Microsoft behind it and is a very useful gauge of your SEO and promotion techniques due to its rapid reaction to changes.

Alan Cole runs http://www.pixelwave.co.uk, a one-person web design studio. His aim is to provide cost effective website design production and maintenance by offering professional web solutions that stand out from the crowd. His services also include copywriting, SEO, hosting, web promotion and training.