### Search engine
How Google, Bing, and other search engines work? 
1. Crawl the web to figure out which pages exist on internet. Crawler bot discovers new pages, and updated pages to understand what information to index 
2. Build index of crawled pages to analyze information in the page so that Google can effectively include them in search results 
3. Rank search results. This is done using complex ML algorithms to understand user's search query intent and match the intent with indexed webpages to provide most relevant and valuable information upfront to user. 

### Factors influencing search ranking
1. Relevance - how closely the content of indexed webpage matches user's intent behind the query 
2. Quality and credibility - how clearly the webpage is presenting information, usability of the site and other factors 
	1. Reputation - What type of other websites link to this site? 
	2. Level of discourse - Is the site promoting violence, or is it promoting content that's causing harm to people?
	3. Level of distortion - What's the deviation between true fact and opinion laid in the website content? If site is clearly laid as satire, it may get ranked up due to the clarity. 
	4. Origination and transparency of ownership - Is website reporting information that originated within itself or is cross-linking or just republishing content that other websites have generated?
3. User engagement - How users engage once they land on the webpage? Do they bounce back to Google/Bing quickly? 
4. Freshness - When was the information last updated? 
5. Location and Language 
6. Page load time - Slow webpages are considered lower in ranking
7. Offensive, harmful or adult content
8. Paid content via sponsored links
9. Personal data and search history
	1. Search query and results click history
	2. User location, language
	3. User device characteristics, browser info

### Search results 
The results can have their layer of visualization and information extraction techniques depending on the user intent and results. 
1. Answers - e.g., scores in a sports event or a match
2. Maps
3. Image and video preview
4. News summary
5. Shopping and commerce links
6. Safe search masked thumbnails
7. Suggestions to improve query prompt or perform follow up search query
8. Generative AI response