"*" means multiplication sign in math.

Because "x" is easily confused with the unknown x and is not easy to type, * is used instead of the multiplication sign.

For example, 3*4=12 and 4*(3+6)=36.

"*" also means a number other than 0 in math, e.g., N* means the set of positive integers, the set of all positive integers.

Expanded Information

The asterisk originated in feudal Europe as a symbol for genealogical printers to indicate the date of birth. It was originally shaped as six asterisks, each of which looked like a teardrop spread out from the center. For this reason, some computer circles call it a "splat" (a gerund, similar to the Chinese word for "snap").

Many cultures have their own unique asterisks. China and Japan use "※", which looks like the Chinese character for "meter". The Arabic asterisk is a hexagram. In some fonts, the asterisk is five asterisks, and the Arabic asterisk is eight asterisks.

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