It is completely automatic, and has no user-definable parameters.
Sample output
Because this template is dependent upon detecting a PAGENAME that is a century, its output can only be seen on a century page. It is impossible to reproduce its results here. If you wish to test it, go to any century and add {{timeline}} to the page.
Special note
Please remember that the word "century" should not be capitalized in the PAGENAME of any new century page that you create.
next up is how to get the thing to work for centuries with 1 digit and 3 digits. Probably will use some kind of #switch. Something like #switch:{{#pos:CenturyNav|c. Then if the position of c is 5 it's a 1 digit century. if it's 7 it's a 3 digit century. and therefore the sub will have to take either the first, or the first 3 digits. </nowiki>