Java is a programming language and computing platform first released by Sun Microsystems in 1995. There are lots of applications and websites that will not work unless you have Java installed, and more are created every day.
IIS is able to impersonate the IUSR_<computername> account because the user name and password for this account are known by IIS. Before returning a page to the client, IIS checks NTFS file and directory permissions to see if the IUSR_<computername> account is allowed access to the file.
Is there any relationship between the fees under the UCRS and the UCR fees? No. Section 4304 of the UCR Act imposes certain fees with respect to the UCRS (for example, on motor carriers first applying for federal authority and on some third parties accessing data in the system). Their only purpose is to provide funds to maintain the UCRS.