Basically Dw230.com is a search engine starting page for Japanese readers and surfers. There are many different search engines on this page, which makes it a good resource. Amazon.com, Google.com, and Yahoo! are among the search bars offered. It has more than this though.

Here is a quote from SlowSeo on the real meaning of Dw230.com: 

• It also has a rank checker for Google PR, Alexa rating, etc." Dw230 Search Engine Optimization (SEO) actually doesn't exist; as this would be optimizing for Google, Yahoo etc. Dw230.com is just a starting page not a search engine.
• If you would like to rank higher on the result pages for DW230.com you should optimize using the normal SEO techniques. And specialy for the Chinese and Asian market read this article on how to submit to Chinese Search Engines.
• China, Taiwan and Japan are huge markets with millions of internet users and it's smart to look into SEO for these countries. Optimizing for DW230.com will not get you anywhere though. Go for Baidu, Google and Yahoo!

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