A common year starting on Saturday is any non-leap year (i.e. a year with 365 days) that begins on Saturday, 1 January, and ends on Saturday, 31 December. Its dominical letter hence is B. The most recent year of such kind was 2022, and the next one will be 2033 in the Gregorian calendar or, likewise, 2023 and 2034 in the obsolete Julian calendar. See below for more.
This is the only common year with three occurrences of Sunday the 13th: those three in this common year occur in February, March, and November. Leap years starting on Tuesday share this characteristic, for the months January, April and July. Any common year that starts on Saturday has only one Friday the 13th: the only one in this common year occurs in May. Leap years starting on Friday share this characteristic.