原文: 网站的相关性，权威性，实用性

大部分关于SEO的文章，容易聚焦在细节问题上，包括我自己的SEO博客。探讨细节问题，容易让初学者知道从哪里下手来优化网站。

但有时候当你掌握了这些技术细节后，需要跳出来，从宏观上看，到底什么样的网站能在搜索引擎排名中有优势。

在我看来，一个网站要想被搜索引擎喜欢并出现在排名的前列，必须要有相关性，权威性，实用性。

第一：网站内容的相关性

也就是用户搜索的关键词与网页内容是否匹配，是否有相关性。

相关性的加强可以通过页面内优化和一小部分链接优化来达到的。包括页面内的关键词位置布局，关键词的强调，通过语义分析得到的相关性，内部链接的安排，网页标题等。外部链接的锚文字，以及链接页的内容，也会对目标网页的相关性产生影响。

内容的相关性是做网站的人最容易控制的，也是最容易被作弊的。第一代的搜索引擎就主要以相关性做判断，但在被钻空子钻的一塌糊涂后，不得不引入权威性的衡量。

第二：网站及网页的权威性

网站或网页的权威性，大部分是由外部链接来衡量。高质量的外部链接越多，网站或网页本身的权威性就越高。另外，域名注册历史，网站的稳定性，隐私权政策等一些细节，也会影响网站的权威性。

另外要注意的是，外部链接对网站权威性的影响是有选择性的，也就是说来自相关内容网站的链接，对提高权威性帮助最大，不相关内容的链接帮助很小。比如我要是在首页上加一个链接到某个美食网站，对对方的权威性几乎没什么帮助。因为很明显，我的网站本身在美食方面就没有什么权威性。

网站的权威性不能被做网站的人完全控制，要想作弊比较费时费力，大量群发现在也越来越容易被检测。但是在某种程度上，权威性还是可以被操作。无论是花钱还是花时间，都可以得到更多的人为链接，现在搜索引擎开始考虑网站的实用性。

第三：网站的实用性

也就是对用户来说，你的网站到底有多大用处？用户是不是喜欢你的网站？

如果用户在你的网站花的时间多，浏览页数多，在不同的时间经常来看你的网站，还加入了书签，并且在不同的网上书签站加了评论，这些都可以帮助搜索引擎理解你的网站对用户的实用性。

搜索引擎的工具条可以帮助收集这类信息，搜索引擎也可以利用越来越多的社会网络网站收集信息。

网站的实用性想作弊就更难，因为你没办法控制用户的电脑和用户的行为方式。当然并不是完全没有可能。不过如果你的网站在相关性，权威性，实用性上都很出色，还都是作弊得来的，这可能性就很低了。

译文: Correlation, Authority and practicability of Websites

After mastering these technical details, however, sometimes you need to have an extension and see what kinds of websites are preponderant in the ranked results of the search engines.

In my opinion, if one site wants to be searched by engines and put in the front rank, it must have correlation, authority and practicability,

Content Correlation of Websites

That means whether there exists match or correlation between the user’s search keywords and the website content.

Optimizing the interior of web pages and some links could improve the correlation, such as the location of the keywords of pages, the stress on the keywords, correlation acquirement by semantic analysis, the arrangement of internal links, and titles of web pages and so on. The anchor text of external links and the content of the linking pages could also effect the correlation of target pages.

 It is easiest to control or cheat the content correlation for the website founders. The first generation search engines worked on the basis of the correlation, and had to introduce the authority after so many cheats came up.

Authority of Websites or Web Pages

The authority of websites or web pages is evaluated mainly by the external links. The more the external links with high quality are, the higher the authority of websites or web pages is. In addition, some details including the register history of domain name, the website stability and privacy policies can also make some impact on the website authority.

It should be noticed that the website authority is selective in the external links. That means the more correlation between the website and the linking websites, the more help for the website authority. For example, adding a link to some delicacies website on my homepage offers little help for the authority of this delicacies website. It’s because my website has no authority about the delicacies.

The website founders don’t have complete control of the website authority. It will take more time and more energy to cheat, and now it’s easier to detect  lots of broadcast. In some degree, however, the authority could be manipulated. More artificial links could be obtained by taking more money or time. So the search engines are considering the website practicability.

Practicability of Websites

That means how much your website could offer the users. Do the users like your website?

If the users spend much time on your website; browse many pages; visit it often; add the bookmarks; and comment on different web bookmarks, your website practicability will be understood better by the search engines.

The search engines make use of its own toolbar and more social network websites to collect these kinds of information.

It’s more difficult to cheat the website practicability now since you can’t control the users’ computers and behaviors. Of course, nothing is impossible, but it’s unlikely to excel in correlation, authority and practicability of your website at the same time by cheating.