搜索引擎优化

The WebConfs website has a very useful list of “Best and Worst Practices for Designing a High Traffic Website.” Basically they collected all the major factors that might affect the search optimization of your site, attributing a score to them. The score ranges from -3, which is very bad for your site, to +3, which is very good. Below you will find a summary of the most important factors:
搜索引擎优化，是网站推广最佳手段，通过以下列表检查你的网站/博客，最高分+3 最差的-3，从而计算你网站的优化程度，当然我们主要关注的是+号的选项，尽量避免负分的出现。(得分越高越好)：
Keywords - 关键词优化
Keyword in title tag (+3)
Keyword in URL (+3)
Keyword density in document (+3)
Keyword in H1 and H2 headings (+3)
Keyword in the beginning of document (+2)
Keyword in ALT tags (+2)
Keyword in Meta tags (+1)
Keyword stuffing (-3)
Links - 链接优化
Anchor text of inbound links (+3)
Origin of inbound links (+3)
Links from similar sites (+3)
Links from .edu and .gov sites (+3)
Anchor text of internal links (+2)
Many outgoing links (-1)
Outbound links to bad neighbors (-3)
Cross-linking (-3)
Meta Tags - Meta标签优化
Description Meta Tag (+1)
Keywords Meta Tag (+1)
Refresh Meta Tag (-1)
Content - 网站内容优化
Unique content (+3)
Frequent updates (+3)
Age of content (+2)
Poor coding or design (-2)
Invisible text (-3)
Doorway pages (-3)
Duplicate content (-3)
Other factors - 其他优化因素
Site accessibility (+3)
Sitemap (+2)
Site size (+2)
Site age (+2)
Top-level domain (+1)
URL length (0)
Hosting downtime (-1)
Flash (-2)
Misused Redirects (-3)