A 

1. name
2. within a namespace and
3. a version.

With these three coordinates the userscript with its code can be addressed. If only the namespace and name is provided, the general type of userscript is typically referenced. For instance a script named 'alter style of page title' will always do just that, although the style, the description, and / or the author documentation may change from version to version. But this is not a strict rule. If the script authors decide to hide the page title, this may not be the result a user of the script is expecting.

Note that the namespace, name, and version cannot be changed for an instance of a userscript. If a userscript is released by the name 'alter style of page title', then this name cannot be changed. The authors may release an additional copy of the script by the name 'hide page title' and delete the 'alter style of page title' script, but these two scripts are two different instances of the userscript type.