Google sandbox alludes to an accepted way of thinking that Google has a channel that places every new site under limitations for a specific measure of time to keep them from positioning in quests
heading tag represents the title of your web page, Header tags are an important factor in on-page SEO because they are used to communicate to the search engines and tell what your website is about.
Google crawler or bots crawl the content of your web and store them when someone search a keyword relevant to your web page content Google put that in front of searcher
A canonical URL is an HTML element that helps webmasters to prevent duplicate content issues by specifying the "canonical" or "preferred" version of a web page as part of search engine optimization. It is described in RFC 6596, which went live in April 2012