The maximum version of Internet Explorer you can have depends on your version of Windows. E.g. Windows 7 users can use Internet Explorer up to version 11, but they cannot upgrade to Edge.
Since early 2016, Microsoft only supports the latest version of IE that is available for a given version of Windows Show archive.org snapshot . If you are using an older version of IE than you could, you will no longer receive security patches for your version.
In April 2017, this means the following: