HstEx has an option to group digits shown in logs and the user interface (Options » Group Digits). For ease of review, numbers with many digits before the decimal mark are divided into groups using a delimiter, with the counting of groups starting from the decimal mark. This delimiter is usually called a thousands separator, because the digits are usually in groups of three (thousands). The most general name for this delimiter is “digit group separator”, because thousands are not always the relevant group. For example, in various countries (e.g., China, India, and Japan), there have been traditional conventions of grouping by 2 or 4 digits. These conventions are still observed in some contexts, although the 3-digit group convention is also well known and often used.