How Do Search Engines Work?

Search engines usage has grown hugely; everyone started using search engines to know the information about their needs, in our daily life we are using search engines through desktop pc’s, laptops, tablet pc’s, mobile devices and etc..,
Search engines operates in three major functions
1. Crawling
2. Indexing
3. Searching
Crawling:
Internet Search Engine works on storing hundreds of millions WebPages information which are available in the internet, A web crawler (also called as spider) is a software program that browses the World Wide Web (www) in automated manner, Web crawler reads the WebPages and jumps in to the another WebPages through the links present in the WebPages in this way it can reach millions of interconnected WebPages. The crawler reads the webpage from the top left to the bottom right, it reads the title of the web page, Meta description, keywords and data present in the webpage, it saves the selected data in index database for use in later queries.
Indexing:
The reason why indexing exist is to deliver the answers for users questions as soon as it found, search engines like Google stores the complete or part of the source page ( referred as a cache) along with the information about the pages and other search engines like Alta vista stores every word of the web page whatever they find.
Searching:
If a user enters query into search engine, the engine checks its index and provides best match results according to its priority, the results contains the short summary of page title, some parts of the texts and the URL (Uniform Resource Locator). The search results of query come according to its indexing data.
Many Search engines work on this process to give best results to the users without disappointing them.
Checkout “How Search works” video by Google Matt Cutts at http://www.youtube.com/watch?v=BNHR6IQJGZs

This Article How Do Search Engine Work copied from Digismak.com

What is Search Engine Optimization

If you type any word in search engines (Google, Yahoo & Bing) query box and press the “Enter” button you get the list of websites that contain the words entered by you.  Generally users visit top websites in the list of search engine results. If you ever find any website that ranking higher than the website that actually you are looking for that is due to powerful Internet Marketing technique called SEO (Search Engine Optimization)

SEO is a technique in Internet marketing, which helps search engines find your website and rank your website greater than the other million websites in a response to the search engine query. So that SEO generates traffic through the search engines.

SEO is a process of improving the appearance of the website or webpage in search engines organic (unpaid or natural or algorithmic) results. If a website ranks higher for the targeted keywords that site generally gain more traffic than the other websites from the search engine users. Search engine optimization targets different types of searches including local search, image search, video search, news search, maps search, blogger search and other types of searches.

As a web marketing strategy, SEO includes how search engine work, what type of searches performing by people, keywords or search words typed by the users in search engines and which search engine are most preferred by the targeted users. Optimization of the website involves editing content with the relevant industry keywords, increasing index pages count in search engines.
If you ask which is good technique to generate more targeted organic traffic, Search engine optimization is the best technique to drive free organic traffic to your website.

This articles "What is Search engine Optimization" Source is Digismak.com