Understanding Search Engines

Intermediary transaction http://www.aliyun.com/zixun/aggregation/6858.html ">seo diagnose Taobao guest cloud host technology Hall

In all network promotion methods, search engines are the most talked about, our promotional tour will start from here.

Indeed, search engines are a very powerful weapon for web promotion and free of charge-but we must first understand them.

We want to know how they work, how to categorize, how to query ... , and search engines are as different as people, so we need to understand their personalities for particularly important engines.

1, two basic words:

Search engine (SearchEngine): By running a software, the software in the network through a variety of links, automatic access to a large number of site pages of information, and according to a certain rule collation, so as to form a database to prepare for inquiries. Such a site (Get information ==> collation Build database ==> provide inquiries) We call it "search engine". And the software used is generally called "Spider", "crawlers" and so on.

Category directory (directory): "Manually" to classify the site to create a database to provide a query, such a site called "Category directory." Typical search engines such as AltaVista, Excite, HotBot, Inktomi, and the most important category is Yahoo.

In fact, whether "search engine" or "category directory", the goal is the same: access to Web site information, set up a database to provide inquiries. But the methods used are different.

"Search Engine" because relies on the software to carry on automatically, therefore, its database capacity is very huge, but along with the query result often imprecise, but "the classification catalog" because relies on the artificial classification, the query obtains the information to be accurate, but collects the content to be very limited.

We usually put these two categories collectively referred to as "search engine", in the following discussion we will be "automatic" search engine mainly, as for "artificial" such as Yahoo, I will be in the "Chinese Yahoo" in the separate discussion.

2, the main search engine:

Seven main search engines and the number of pages included: Engine alta Vista Northern Light Inktomi Excite Lycos Web Crawler pages (million pages) 1501251105550452 (above data is February 1, 1999 statistic)

3, search engine work three steps:

The first step is to "Spider" software to visit a site, and through the link to read the site's pages, and "Spider" will automatically return to the site to check the changes, the "Spider" to obtain the site information to form a huge network of repositories, As a backup of the site has been visited on the entire network, of course not all of the content is recorded. This is what we call the database. The third step is to query the service. This is done through the query software, when you enter the query content, the software will find the relevant content in its database, and then follow the "it" rules to sort.

4, search engine in the query is how to rank: the most important is based on the content of a site and query the degree of relevance of the word, but a site content search engine is how to determine it? --Title, Keywords (Keywords), description (Description), content at the beginning of the page, and the degree of association between the content itself. And most of the search engines now support metatag.

Another major factor is the degree to which a site is associated across the network, that is, the number of times a site appears on other sites on the network (linkpopularity).

Although different search engines have their own "rules of the game", please remember the word "relevance", including both inside and outside the station (the entire network).