反向链接是指A站通过域名或锚文本指向B站，从而使网站权重得到提升。

• 在论坛签名内加上网站名，发言时就会带上网站链接
• 创建博客，在更新的文章内加上网址
• 到各个相关门户投稿，并加上网站链接
• 购买链接，这种方法不太稳定，不建议采用
• 在别人博客留言
• 和其他网站交换友情链接

A backlink for a given web resource is a link from some other website (the referrer) to that web resource (the referent). A web resource may be (for example) a website, web page, or web directory.

A backlink is a reference comparable to a citation. The quantity and sources of backlinks for a web page are among the factors that Google's PageRank algorithm evaluates in order to estimate how important the page is. The PageRank score is, in turn, one of the variables that Google Search uses to determine how high a web page should go in search results. This weighting of backlinks is analogous to citation analysis of books, scholarly papers, and academic journals.