What is the difference between SEO and SEM ?

[daviddakarai]

SEM or Search Engine Marketing encompasses all aspects of search marketing including PPC, SEO, affiliate programs, social media campaigns, etc.

Through SEM (PPC) paid search advertising you essentially buy advertising space in the search engine results. So instead of trying to rank higher and get free traffic you pay to appear in front of the searches.

The most well-known advertising agency for PSA is Google Adwords. Through Google adwords you can get your ads appear in the Google search results and you pay only for the clicks on your ads. This is also the reason why the whole process is called Pay-per-click or PPC. Bing and Yahoo have a similar system but it not so successful and widely known as Adwords.

Search Engine Optimization (SEO)

SEO is the process of optimizing your web site for the purpose of getting free traffic from search engines. An optimized web site is more easily understood by Search engine crawlers, so there are more chances of ranking higher in SERPS.