Search Engine Marketing (SEM) is getting new customers from search engines like Google, Bing etc.

Search Engine Optimisation (SEO) is on-site and off-site work to get your web site listed and ranking in response to search engine keywords relevant to your product / service.

Pay Per Click (PPC) is pay for performance (click thru) advertising on a search engine. e.g. Google Adwords.

So which one provides small business owners a better return on investment?

Here is an article published on AustralianBusinessSuccess on the topic of Search EngineMarketing – SEO versus PPC.