This seems to be a hot topic lately- Google identifying a 'home' page as, for example www.mysite.com/index. After all, this is typically where the name of your page is defined by your title tag. However, the term index can refer to several different things in the context of the web.
In this case, what we're seeing is how Google identifies an Index page. While we recognize it as a 'home' page, an index page is the identification of the main (or home) page of a web site.
To put this into context, search engines don't actually search the entire web. Truth be told, they operate from enormous "indexes" of information: videos, documents, web pages, etc. When the search engines send out software (also known as search engine spiders) to crawl the web, they are actively "indexing" new content to be included in that particular search engine's index.
So if you're curious why your home page shows up as www.mysite.com/index, it's because Google has already 'indexed' your home page.
I hope that helps!
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