Stardates Explained - 19981002.1353

You don't understand the startdates?

Take, for example, 19981002.1353

Let me stick some spaces in some helpful places:

1998 10 02 . 13 53

That better?

19981002 means 2nd October 1998, and 1353 is in 24-hour clock format, IE 1:53PM

Stardates in the Star Trek universe work in an entirely different way. Wikipedia has a good explanation on how Stardates work.