Guest posting is best factors in SEO because that facots only consider high quality contant, nowadays google accpet only unique and informative content crawle.. You can search in Google.com lot's of website available..
Guest posting is one of the most important parts of marketing. Find topic relevant blogs and ask them to become their author. But, you'll need to have high quality articles (not self-promotions) to qualify.
SEM stands for the Search Engine Marketing. We can call it ppc program. Google AdWords, Yahoo Ad and MSN Ad center are the example of SEM.
SEO stands for the search engine optimization. It can divided in two parts:
On page seo (seo friendly website, unique content, sitemap, all meta tags etc.)
Off page seo (directory submission, social bookmarking, forum posting, article submission, guest posting, etc.)
SMO stands for the social media optization, we can promote our business with the help of the social networking sites like facebook, g+, twitter, pininterest etc.
Guest posting refers to the post our blog post on another persons high traffic blog by contacting that person. we can also submit their post on our blog. so it helps to get the traffic on our blog and helps to increase the page rank of our blog.