SEO is the method of developing, making better and popularize website, for raising the number of visitors from search engine. The way of receiving traffic, through the: free, organic, editorial or natural in search results.
It is not just concerning “engines.” It’s concerning creating your web site higher for people too.
Optimization is one of the online marketing strategies, where seo have to keep check on way of search engine works, keywords used for search, and users preferred which search engines.
The mainstream of traffic is taken by key profitable engine Google, Bing and Yahoo. Even though internet can make link to your website, search engines are the most important technique of reaching for most potential users. Keywords play an important role which can be used to makes it higher rank on targeted users. Seo manage all these functions to make your site more popular.
Techniques of SEO
Develop your title tags
Form convincing Meta descriptions
Exclusive content
Make use of keywords
Add sitemap
Create internal links between pages
Bring up to date your site frequently
Methods
> Indexed
> Prevent Crawling
> Rising Prominence

SEM (SEARCH ENGINE MARKETING)
It is one of the processes of online marketing, which engage in advancement of website by raising the visibility of page at the time of search. Purchasing traffic by paid search listing and also uses organic search results.
Organic search: increasing search rank in natural form, through keywords or turn of phrase.
Pay per click advertising: bid the price wants to pay per click, which were post by you for your site. Content sites ordinarily charge a set worth per click instead of use a bidding system.
Google AD words used in pay per click are admired mainly by everyone, as it is the one of the trendy type of advertising between small businesses. The reason behind this is, to some extent, goodwill of Google and not so High cost for business owner.
In PPC, you pay only, when somebody clicks your ad and look up your web site. It simpler to use and give better results, with every click to their adv, they also get known to the online users
Paid inclusion: associate with search engine getting price for the inclusion in their search pages.