Its most important part of seo. A keyword is essentially any word or phrase you use when searching with a search engine. The search engine does its best to match your words with the words on websites.SEO involves the strategic placement of keywords throughout your website. You can discover which words and phrases you should be optimizing for by conducting keyword research using a tool such as Google AdWords Keyword Tool.
There are many SEO company provide this service.For Example, TheWebPole.com, XnYnZ.com, TuckTail.com Here they provide google keyword generator with Search Engine Visibility service. This will helps to list the top search terms for any topic in 40 Language.