English: Common decimal separatorsː The period and comma (decimal point and decimal comma) are the two most commonly used types of decimal separators in the world. Either is also sometimes used in combination with the other, with one acting as a decimal separator and the other as a digit grouping separator (most commonly thousands separator). However, since 2003 SI recommends a space being used as a thousands separator, with either the decimal point or decimal comma as the decimal separator.