(1) See Asterisk PBX.
(2) In programming, the asterisk or "star" symbol (*) means multiplication. For example, 10 * 7 means 10 multiplied by 7. The * is also a key on computer keypads for entering expressions using multiplication. Sometimes called a "splat," the asterisk is also used in programming as a dereferencing symbol. See dereference and star-dot-star.
(3) On calculator keyboards, the * key is the total key, and the "X" key is the multiplication key.
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