SEM(Search Engine Marketing) includes promotion of websites from both paid search results and organic search results which increases the visibility of website in search engine resulting pages (SERPs). SEM is also referred to as cost per click(CPC) or pay per click (PPC) marketing.
There are two ways to show up in search results
1. Paid Search / CPC / PPC Listings: It has a simple concept of marketing that is if you pay , you get listed and when you stop paying your website is in deep pool of nowhere.
2. Editorial / Organic / Natural Listings: the best search engines in world like Google & Bing have editorial or natural or organic listings. These listing requires strong content which explains the title of the page with out spamming.