answer:There are a few limitations/requirements for websites to show up in Google. Google gathers information through a web crawler. Basically, a computer visits a webpage, reads everything on that page, and then it follows the links on that page to find other webpages. In order to be “discovered,” a webpage must be linked to the rest of the internet. If no other websites link to your website, then Google will have no way of finding it. Any content hidden behind logins will not be seen. Any websites which explicitely disallow Google will also not be visible. A big thing is dynamic content, which is also invisible because it can only be found using certain queries, which Google does not know.