Before finding out how keywords work, you first need a quick overview of how Web sites are cataloged and then returned as search results. The way things go, you first put up a Web site. It doesn’t have to be anything fancy maybe it’s your personal blog about your busybody Aunt Louise and how crazy she makes you, or it could be a serious site about how frogs hibernate in the muck at the bottom of ponds during winter. The topic of your Web site doesn’t matter, but you have to get it on the Internet.
After you put up a Web site, a search crawler a specialized software program that examines Web sites and categorizes them by keyword finds your Web site. Search crawlers are designed to crawl every Web site within parameters that are outlined by the search crawler’s designer. A designer could order a search crawler to, say, examine Web sites contained on a list drawn by the designer.
The crawler’s first stop is the first Web page of the first Web site on the designer’s list. The crawler reads through the pages of the Web site, looking at each word on the site
Crawlers also look at what words are used together. For example, cosmetic makeup is different from exam makeup, but the crawler knows that makeup is used in two completely different ways because it looks at the words surrounding it.
While the crawler makes its way through a site, it records the number of times a keyword, a keyphrase, or a set of keywords is used on the site. If exam makeup is used in the title and then three times in a 300-word section of text, it’s probably a good bet that the Web site being crawled is about makeup exams. Of course,the search engine crawler isn’t betting on anything. The crawler’s like the skeptic who doesn’t count on anything that’s not immediately visible and physically touchable. Exam makeup may be there, but it needs proof!
The crawler uses a very lengthy and complicated algorithm as its search formula. The algorithm compares the number of times a keyword is used to indicators that tell it if that keyword is important on the Web site. Like color coding, that algorithm makes it possible to define a Web site in terms of how it relates to a specific topic.
Algorithms in general are computer programs that systematically solve problems such as determining how many times a keyword is used on a Web site. They’re complicated creatures, highly technical in nature, and they are a search engine’s lifeblood which is why they’re so jealously guarded. Just try to pry Google’s secret algorithm from their tightly clenched fist and see where that gets you.The crawler takes a stab at what your Web site’s all about by registering the site’s keywords.
The crawler then takes another look at the site, this time considering those keywords in the context of the Web site not just the keywords but also things like keyword placement (where on the site the words appear), the alternative text you put in for graphics (the stuff that shows up if the graphic won’t load), and the links into and out of the Web site.
After looking at all these elements and many others (some search engines use over 100 different considerations), the crawler makes a determination about where in the great scheme of things a particular Web site belongs.That information is then stored in a database the size of Manhattan.
Okay, it’s not really the size of Manhattan, but it’s huge. Way larger than any database you’ve ever encountered before.
After the Web site’s cataloged, it can be pushed to visitors that do a search based on keywords related to the main keyword of the Web page.That’s another algorithm altogether. That algorithm cross-references the search that a user makes with the data stored in the database to determine which sites of the billions of cataloged sites are the best fit for the keyword or phrase that the searcher used.
In other words, your Web site basically boils down to the keywords on which it’s built. To rank successfully in any search engine, you not only need the right keywords but you also need keywords that are closely associated with the topic of your Web site. Those keywords also need to be at the right places on your Web site. If they’re not, the search crawler won’t feel completely confident about which particular section of the database is the proper home for your site so the site might be put lower in the rankings behind many other (perhaps far less relevant) sites.