Excel Summing up numbers (SUM, SUMIF, SUMIFS)

SUM =SUM(number1, [number2], …) Adds all the numbers in a range of cells
SUMIF =SUMIF(range, criteria, [sum_range]) Adds the cells specified by a given condition or criteria
SUMIFS =SUMIFS(sum_range, criteria_range1, criteria1, …) Adds the cells specified by a given set of conditions or criteria

SUM

SUMIF

SUMIFS