What are the differences between SEO, SMM, SMO, and SEM?

So many acronyms with seemingly similar goals, lets break down what each mean:

 

SEO - This term stands for Search Engine Optimization. Essentially, SEO is the process of optimizing a website to rank higher in search engines.  SEO aims to gain traffic and brand awareness through organic search, rather than paid promotion.

 

SEM – This term stands for Search Engine Marketing. SEM works by placing Paid Ads under Google, Bing, and Yahoo with specific keywords and can also be known as non-organic search. worked under Paid Ad's which placed under Google, Bing, Yahoo as AD's with specific keywords and also known as Non-Organic Search. SEO can be included under the broad term of SEM. 

 

SMM – This term stands for Social Media Marketing. SMM tactics use paid advertisements on social media sites like Facebook, Twitter, YouTube, etc. 

 

SMO – This term stands for Social Media Optimization. SMO aims to optimize a website and its content in terms of sharing across social media and networking sites. By using a number of social media outlets and communities to generate publicity to increase the awareness of brand, product, or event. It is similar to SEO.

Source: http://goo.gl/xHHW7w