Also this option may be useful to set custom event recurrence. You may set up events to remind you something periodically, e.g. take medication, take a coffee-break, etc.

Weekly event option specifies weekly recurrence.

You may choose days of the week when the event will appear and set the week of occurence: current week, next week, every week, etc. Additionally you may specify Repeat event option to be reminded several times.

Choose Monthly or yearly event option if you would like to set up event with monthly or yearly recurrence (monthly report, payment processing, birthday, holiday, etc.).

Choose months when the event will appear. Event will appear every year in the months specified. You may set monthly/yearly recurrence either by date (day of month) or by day of week. Date option gives you the possiblity to select either the exact date when the event will appear (e.g. 15, 24) or day of months counted from the end of month (last day of month, last -3 day of month, etc.).
Day of week option is useful for creating holiday reminders.

You may choose event to run for example on the 3rd Saturday in May, fourth Thursday in November, etc. Additionally you may specify Repeat event option to be reminded several times.