To understand, how a search engine works, we can divide the work of search engines into three different stages: crawling, indexing, and retrieval.

Crawling: It is performed by software robots called web spiders or web crawlers. Each search engine has its web spiders to perform crawling. In this step, the spiders visit websites or web pages and read them and follow the links to other web pages of the site. Thus by crawling, they can find out what is published on the World Wide Web. Once the crawler visits a page, it makes a copy of that page and adds its URL to the index.

The web spider generally starts crawling with heavily used servers and popular web pages. It follows the route determined by the link structure and finds new interconnected documents through new links. It also revisits the previous sites to check for the changes or updates in the web pages. If changes are found, it makes a copy of the changes to update the index.

Indexing: It involves building an index after crawling all websites or web pages found on the World Wide Web. An index of the crawled sites is made based on the type and quality of information provided by them and stored in huge storage facilities. It is like a book that contains a copy of each webpage crawled by the spider. Thus, it collects and organizes the information from all over the internet.

Retrieval: In this step, the search engine responds to the search queries made by the users by providing a list of websites with relevant answers or information in a particular order. It keeps the relevant websites, which offer unique and original information, on the top of the search engine result pages. So, whenever, a user performs an online search, the search engine searches its database for the websites or web pages with relevant information and make a list of these sites based on their relevancy and present this list to the users on the search engine result pages.

The anchor tag is used to make click-able text written on a hyperlink, i.e., it is a clickable text in a hyperlink. It enhances the user experience as it takes the users directly to a specific area of a webpage. They are not required to scroll down the information to find a particular section. So, it is a way to improve navigation.

It also enables webmasters to keep things in order as there is no need of creating different web pages or splitting up a document. Google also sends users to a specific part of your page using this tag. You can attach anchor tag to a word or a phrase. It takes the reader down to a different section of the page instead of another page. When you use this tag, you create a unique URL on the same page.

• KEYWORD STUFFING : The search engines study the keywords included in a webpage to index the webpage or a site. So, some people increase the keyword density in their web pages to get a higher ranking. Keywords should be 2 to 4 % of the total world count, increasing keyword density beyond this is known as black hat SEO as it is against the SEO guidelines of Google.
• CLOAKING : In this technique, the web pages are coded are in such a way that visitors see different content in a webpage and search engines see different content on the same webpage. Increasing ranking in this way is also against the guidelines of search engine.
• DOORWAY PAGES: These pages are rich in keywords and do not have quality content and relevant information. They redirect users to a different page to increase the ranking of that page. It is also against the guidelines of Google.
• HIDDEN TEST:is the text that can be viewed by the search engine, but visitors cannot view. It is used to include irrelevant keywords and hide text or links to increase the keyword density and improve the internal link structure.
• ARTICAL SPINING : It refers to rewriting an article multiple times to produce its different copies in such a way that each copy looks different from other copies and is treated as a new article.
• DUPLICATE CONTENT :It is the content that is copied from one site and uploaded to another site. It is known as plagiarism.

• A website made on flash. or
• A website made on HTML 5.

The content presented in a flash website is hard to parse by search engines, so, it is always preferred to build a website in HTML for better SEO prospective.

Page title, H1, Body text or content, Meta title, Meta description, Anchor links and Image Alt Tags are some of the most important areas where we can include our keywords for the SEO purpose.

A webmaster is a free service by Google which provides free Indexing data, backlinks information, crawl errors, search queries, CTR, website malware errors and submits the XML sitemap. It is a collection of SEO tools that allow you to control your site in Google as well as allows Google to communicate with webmasters. For example, if anything goes wrong like crawling mistakes, plenty of 404 pages, manual penalties, and malware identified, Google will speak to you through this tool. If you use GWT, you don't need to use some other costlier tools. So, it is a free toolset that helps you understand what is going on with your site by providing useful information about your site.

Many search engines use programs called spiders to index websites. The spiders are also known as crawlers or robots. They act as automatic date searching tools that visit every site to find new or updated web pages and links. This process is called web crawling. Spiders follow hyperlinks and gather textual and meta information for the search engine databases. They collect as much information as they can before relaying to the server of the search engine.

Spiders may also rate the content being indexed to help the search engine determine relevancy levels to a search. They are called spiders as they visit many sites simultaneously, i.e. their legs keep spanning a large area of the web. All search engines use spiders to revise and build their indexes.

Meta tags are the HTML tags that are used to provide information about the content of a webpage. They are the basic elements of SEO. Meta tags are incorporated in the "head" section of HTML, e.g. Meta tags are placed here.

The Meta tags are of three types. Each tag provides specific information about the content of the page. For example:

• Title Tag: It is the most important of all the Meta tags. It tells search engines about the title your webpage, and it is displayed in search engine listings above the URL of your webpage or website. For example:
• Description Meta tag: The summary of your site or webpage is incorporated in this tag. It enables the search engine to display a brief description of your page in the SERPs. Through this tag, you tell users what your site is all about and what you are offering. For example:
• Keywords Meta tag: In this tag, you place all of your main keywords and phrases that describe the content of your webpage. For example:

A title tag is an HTML element that is used to specify the title of a page. It is displayed on search engine result pages as a clickable heading just above the URL and at the top of the browser.

In SEO, the title tag is significant. It is highly recommended to include a unique and relevant title that correctly describes the content of a webpage or a website. Thus, it tells the users and search engines about the nature or type of information contained in your webpage.

An ideal title should be between 50 and 60 characters long. You can also place your primary keywords at the start of your title and put the least important keywords at the end. It is the first thing that a search engine analyzes before ranking your webpage.

No, Google does not use the keyword meta tags in web search rankings. It is believed that Google ignores the meta tags keywords due to their misuse.