It's index.html (lowercase i). That's a commonly used name for the index document. There are others in use, like index.htm, index.php, default.htm(l), start.htm(l). But in the end, your hosting provider can use anything they like via a server directive. It should be in their FAQ.
Note you do not absolutely need it, but for any other document you would have to specify its name in the URL. Only the index document is found automatically by the browser.
Without index document and without specification of a document name, you will get an index listing (listing of all files) of that directory, or, if index listings are forbidden, a 403 Forbidden error.
Note you do not absolutely need it, but for any other document you would have to specify its name in the URL. Only the index document is found automatically by the browser.
Without index document and without specification of a document name, you will get an index listing (listing of all files) of that directory, or, if index listings are forbidden, a 403 Forbidden error.