SEO is Cost Effective: More than 80% of Internet users don't have the intention of purchasing any product or service when using search engines.
Then why should one pay money for clicking their ads? Long term positioning One of the great benefit of SEO Optimization is that Once a website is promoted through SEO, it should stay on the Positioned rank for long time.
On the other hand results through PPC (Pay Per Click).
Varies according to the biding on the keywords.
If someone has bid more for a keyword his result will appear first.
Cross-Browser Compatibility SEO is not restricted to a particular search engine, Like PPC.
its optimized in all the search engines, while PPC is restricted if you choose ad word you are is the list of sponsor listing of Google only, not in all the search engines.
Measurable results The best thing about SEO is that you can quantify the results of SEO.
By search engines results, visitor conversion and the other factors while it is not possible to know which click was valid or invalid.
Pay per click PPC is a campaign in which advertisers use search engines to advertise their products.
Your advertising costs are related to a number of factors including keyword competitiveness and ad placement.
Example is Google AD World.
The advertiser's total advertisement cost depends on the total number of clicks on his ads.
Whenever some user click on his add advertiser has too pay a amount for which he has bid for.
When any user searches any keyword in the search engine Ex.
Google, it displays search results on a search result page.
One of them is the result is known as organic search which appears on your left hand side.
The other section of the result page is called the sponsored links, which appear on your right hand side.
Conclusion: I personally believes that SEO is more effective then PPC.
As once your website is optimized it will stay in the search ranking for long while results of PPC Changes according to the bid value.