These are for expenses that you have every single month — like electric bill or groceries. At the beginning of each new month, you get a clean slate. Overspent or underspent money doesn’t roll over from one month to the next.
These are for expenses that you have at least once a year, but not necessarily every month — like gym membership or car maintenance. The unspent money for each category rolls over from one month to the next. This allows you to save up for larger expenses, like your vacation or Christmas.
You can set up or change the amount you’re planning to spend in all of 2011 on your irregular categories here: https://pearbudget.com/set_up_2011.