Before SEO Let's understand SE ie Search Engine
A search engine is a special kind of website that helps users find web pages from other websites.
Don't confuse Chorme, Mozilla, Safari etc are not search engines they are browsers a piece of software that retrieves and displays web pages based on the Ranking, thats it.
Search Engine Optimization
In simple terms, it means the process of improving website visibility in search engines(Google, Microsoft bing)
Earning backlinks is an essential component of off-site SEO.
How does SEO work?
Search engines such as (Google, Microsoft bing, and other) use bots to crawl pages on the web and collect information about those pages and putting them in an index.
index: like a book index in our case webpage = book
A bot -- is short form of robot and also called an internet bot -- is a computer program are made from sets of algorithms to perform certain tasks used to automate certain tasks on the Internet.
How do bots work?
Normally, bots operate over a network. They communicate with one another using internet-based services.
tasks include: gathering content from websites
Types of bots
many types but for SEO we use crawler in case of google crawler is Googlebot.
Crawlers. Also known as web crawlers, these bots access websites and gather content for indexes in search engines, such as Microsoft Edge.
HTML tags tell search engines which versions of your content are the original ones.