SEO (search engine optimization) a process to increase traffic rank and popularity of your site, and a process to improve keyword rank on relevant searching result in search engine.
Yup i agree..There are several methods to increase traffic such as Article submission,Social networking,Affiliate marketing etc..
They play a vital role in improving traffic.But these all will take little time .
If you want to increase your page rank even more faster,paid SEO service is the best one.
I used the SEV(Search Engine Visibility) service available in http://www.thewebpole.com
It will promote your site by submitting it in 100 search engines,directories and provide suggested keywords.Hence the website and page rank increases soon.