Difference between SEO,SEM and SMO?

[shalini]

Search engine optimization & search engine marketing both the terms actually refer to two different parts of the same marketing scheme.SEM is a much broader term than SEO, and actually includes SEO as one of its techniques. SEM is all that a company can do to advertise itself on a search engine, including paid inclusion and other ads.

[ivan]

SEM is a much broader term than SEO, and actually includes SEO as one of its techniques. SEM is all that a company can do to advertise itself on a search engine, including paid inclusion and other ads. - Search engine marketing (SEM) is the act of marketing a website via search engines, whether by improving rank in organic or natural listings, paid or sponsored listings or a combination of both. - Social media optimization (SMO) Social Media Optimization is the methodization of social media activity with the intent of attracting unique visitors to website content.

[andrewjohn]

Seo is used to increase your website ranking. In the Seo on page and off page optimization two activity includes.in the seo off page the link building is the most important way to get more back link to your web site.Seo is the long term process to get back links but it is free inclusion.
Sem:A form of internet marketing that seeks to promote websites by increasing their visibility in search engine result pages (SERPs).  SEM methods include: search engine optimization (SEO), paid placement (contextual advertising, digital asset optimization, and paid inclusion).
Smo; SMO is the social media optimization which is used to get traffic to your website through the social media networking sites.

[Smith Jones]

 SEM is the main and basic marketing method for the promotion of the business. SEM have main two part for getting result as one is the paid way which include PPC or another method CPC. And SEO is the SEO which is the unpaid method means it is the way to get the results naturally as free of cost and effectively also.

SMO is the part of SEO. Social media optimization is a great techniques by which you can get more traffic and business for the website.

Have a nice day !!!

Smith Jones 

[ella.boswell]

SEO - Is optimizing the page to be easily found and indexable by search engines. This is everything from content writing to getting backlinks.

SEM - Is bidding on keywords through tools like Google AdWords. This can be extremely expensive and time consuming, and should probably only be a short term solution until your site is performing well organically.

SMO - Is setting up and participating in various Social Media sites, like Facebook, Digg, Delicious, etc. The purpose here is to build commuinities of fans and spread the word on your updated content.

[jeffreyrogers]

SEO - Is optimizing the page to be easily found and indexable by search engines. This is everything from content writing to getting backlinks.
SEM - Is bidding on keywords through tools like Google AdWords. This can be extremely expensive and time consuming, and should probably only be a short term solution until your site is performing well organically.
SMO - Is setting up and participating in various Social Media sites, like Facebook, Digg, Delicious, etc. The purpose here is to build commuinities of fans and spread the word on your updated content.