How does an search engine actually works? What Is SEM?

Search engines are programs that regularly crawl the internet to index web pages into a database that internet users will be able to search through the use of keywords. They work by sending out spiders (also called bots or robots) to automatically browse as many documents as possible using hyperlinks.

Also there's another program, called an indexer, that reads these documents and creates databases with all the relevant keywords featured in each document.

What makes SEM such a complex discipline is that each engine uses a proprietary algorithm to create it’s index. To build a search engine optimised website, it is important to have some knowledge of the most important indexing standards.

SEO stands for Search Engine Optimisation. It consists of improving a website for it to comply with search engines requirements.

SEM stands for Search Engine Marketing. It consists of every technique used to promote a website via search engines, whether this be improving rank in search results, purchasing paid listings or other search engine related activities.