5 Shanghai dragon based more reading
1. to prevent untrusted content, is the most common spam messages and comments on the blog in order to get outside the chain of spam links, in order to prevent the page to page and site some garbage.
) pruningThe abuse of
nofollow HTML (meta) content meta tag attributes and link tag (a) of a value of the rel attribute, tells the machine (crawler) without tracking the target page, in order to fight against the blogspam (blog spam messages), noble baby recommend the use of nofollow, tell the search engine crawlers without grasping the target page. At the same time tell the current page search engine without the Pagerank transfer to the target page. But if you are through sitemap directly to the page, or crawler crawling, here nofollow is the current page an attitude to the target page, other pages of the target page does not represent the attitude.
meta for 1. yuan, tell the spider Tags: all the links on this page without tracing.
nofollow has three main functions:
3. guide crawler effective web crawler: avoid meaningless page, affecting the efficiency of crawler.
The use of nofollow
4 Shanghai dragon
2. for a Tags: login, tell the spider this page without tracing.
nofollow has two kinds of usage:
3 PR (Pagerank sculpting
nofollow, Shanghai dragon in order to achieve maximum search engine optimization, through the nofollow to control the flow of PR, can be a very good optimization of some specific pages. Of course, this optimization is more suitable for some has accumulated a considerable number of the old site of PR. In order to prevent the abuse of the PR and nofollow trim, noble baby has weakened the role of the nofollow, the previous nofollow NOT only will not cause PR flow, at the same time will not cause the loss of PR, nofollow now although the provisions will not cause PR to the target page, but the target page flow will lose the original. For example, the current page PR is 1, and there are 10 > page chain
2. paid links: in order to prevent the influence of paid links nobility baby ranking search results, noble baby recommend using the nofollow property.
PR (Pagerank Sculpting