As per my knowledge SEM means Search Engine Marketing and it is one of the part of whole Search Engine Optimization process.

SEM stands for �search engine marketing.� It is the process of gaining traffic from or visibility on search engines.

SEM Search Engine Marketing is the abbreviation, meaning in Chinese is the Search Engine Marketing. SEM is a new kind of Internet marketing form. SEM have done is a comprehensive and effective use of search engine network marketing and promotion. SEM the pursuit of the highest cost performance, with the smallest input, won the largest from search engine traffic, and produce commercial value.

Search engine marketing, (SEM), is a form of Internet marketing that seeks to promote websites by increasing their visibility in search engine result pages (SERPs) through the use of paid placement, contextual advertising, and paid inclusion.

SEM stands for search engine marketing.SEM is the type of marketing that include the both paid search result like as adwords and organic search result like SEO.

Search Engine Marketing, a technique where you use PPC and SEO tricks to get customers/clients/visitors

SEM also known as Search engine marketing is a form of Internet marketing that seeks to increase websites visibility in search engine result pages through the use of search engine optimisation, search engine advertising/Pay pewr click advertising, paid inclusion and also a few other methods

SEM is usually used to describe the immediate, money-backed portion of search engine marketing that commonly takes the shape of PPC search engine results page ads in one form or another.