Root URL
A root URL is the start or index page of a domain on a web server. Colloquially, many users call the homepage the “root URL” as well. Since root means “the basic cause, source, or origin of something,” (Oxford English Dictionary), root URL could therefore also be considered the “source directory” or “source URL” for all subpages of a domain.
Storing files in the root
If files are stored in the “root” of a web server, they are always listed right after the slash and after the web address.
Example:
An image file named fish.jpg is stored in the server’s root directory on www.sample.com. After uploading, it can then be accessed under www.sample.com/fish.jpg if no further restrictions exist for access to the root such as a password prompt.
The root URL is therefore correctly considered the whole URL including a slash, for example
www.fish.com/
Effects on traffic
The user assumes that it does not matter if you enter a URL with or without slash, after all, the desired site will be retrieved in both cases. However, it does matter for the web server. There is an invisible process running in the background. The browser notes that under www.sample.com no site is accessible. It must get information from the web server about which directory has been defined as root directory. This is done via a redirect to the root URL. If a website is not called via the root URL, this causes an increased burden on the web server. Increased traffic thus can cause increased waiting times.
Relevance to search engine optimization
If a URL version is specified as the root URL, only these should be indexed. In extreme cases, the homepage of a website can be available under three or more different URLs. This poses a risk of duplicate content, since the same content can be accessed via different URLs.
Example:
* http://www.mydomain.com * http://mydomain.com * http://www.mydomain.com.de/index.php
To avoid errors, the webmaster should opt for a version of the homepage and redirect all other versions via 301-redirect to the original version.
At the same time, this circumstance should also be observed when it comes to link building. If links are set referring to the homepage, they should either directly refer to the domain followed by a slash or in a different root directory, the corresponding root URL. This also applies to entries in search engines or directories. With appropriate visibility much traffic will come from those and if there is any error in root URL entry, the traffic would have to be redirected every time. Alternatively, redirects should be set up for all URLs that refer to the homepage.