Basics SEO

The Different Types of Search Engines

Although the term “search engine” is often used indiscriminately to describe crawler-based search engines, human-powered directories, and everything in between, they are not all the same. Each type of “search engine” gathers and ranks listings in radically different ways.


Crawler-based search engines such as Google, Yahoo and Bing, compile their listings automatically. They “crawl” or “spider” the web, and people search through their listings. These listings are what make up the search engine’s index or catalogue. You can think of the index as a massive electronic filing cabinet containing a copy of every web page the spider finds. Because spiders scour the web on a regular basis, any changes you make to a website, or links to or from your own website, may affect your search engine ranking.

It is also important to remember that it may take a while for a spidered page to be added to the index. Until that happens, it is not available to those searching with a search engine.

Search Engine Optimization (SEO) refers to making changes to a website so that it can attain higher search engine positions for specific keyphrases in organic results.

Organic results refer to the regular search engine results displayed by crawler-based search engines; as opposed to sponsored results which are paid advertising (see below).


Directories such as Open Directory depend on human editors to compile their listings. Webmasters submit an address, title, and a brief description of their site, and then editors review the submission. Unless you sign up for a paid inclusion program, it may take months for your website to be reviewed. Even then, there’s no guarantee that your website will be accepted.

After a website makes it into a directory however, it is generally very difficult to change its search engine ranking. So before you submit to a directory, spend some time working on your titles and descriptions or hire a professional to submit to directories for you.

Paid Inclusion

Some directories offer some form of paid inclusion. Paid inclusion guarantees your website is reviewed and/or indexed promptly. Keep in mind that these directories and search engines usually still allow people to submit for free; it just takes longer.

Pay Per Click (sponsored results)

PPC advertising is the name for the ads you see at the top or on the right of the organic results in most search engines. Services such as Google AdWords, and Bing Ads allow you to pay to show your ads on search engine results pages. How much you pay (your bid), along with the click-through rate of the ad (CTR) and the relevance of the landing page, determine the ranking of your PPC ads.

There are companies such as Red Carpet Web Promotion that set up and manage PPC campaigns for companies that bid on many keyphrases (which can number in the thousands). Contact Red Carpet Web Promotion if this or other web promotion services interest you.