In mathematics, the * sign can actually mean a number of things. First of all, in programming and generally computers, the * sign denote multiplication. This is mostly a convention that has arisen due to the layout of our keyboards and the signs that are easily available.

However, in the mathematical world, the * sign actually more seldom mean multiplication than it means other things. Most commonly it is found in the mathematical operation known as "Convolution". A convolution is an operation that arises in many areas within physics and electronics and is also extremely heavily used in the field of computer imaging for applying various filters. A convolution refers to an operation between two functions which produces a third function. The third function is usually visualized as a modified version of one of the input functions, typically representing an overlap of their areas, in some dimensionality.

After the convolution, the * sign also commonly appear to indicate the complex conjugate of an imaginary number. This notation is very useful as we do not have to use multiple variables to denote the same number as its complex conjugate is strictly defined.

The * sign also appears when denoting the adjoint of either an operator, or a matrix. Again these are properties of pure mathematical characteristics that may seem dry but are highly useful in physics.

Above are only 3 examples of the most commonly used notations in mathematics. As you see, the use of * sign to denote multiplication truly is only an artifact that we have in computers in lack of better symbols and conventions. Noone would write * to denote multiplication in a printed equation in either articles or books (anything on print) or by hand on paper.

It means multiplication and was originally used in programming to indicate multiplication.

In an equation, humans understand "xy" as meaning x multiplied by y or "a x b" as meaning a multiplied by b.

A computer needs "delimiters" to allow parsing or splitting up of equations or strings into pieces which can be processed. If "x" was used, the computer wouldn't be able to understand whether a variable "x" or multiplication was implied. Similarly if two variables were placed beside each other e.g. ab , the computer wouldn't understand.

This is why "back slashes", "dots" etc are used in addresses of websites.

The asterisk in mathematics mean multiplication. You cna replace the times sign (x) with (*) to mean the same thing. So

5 x 2 = 10 is the same as 5 * 2 = 10

Depends on what subject, in geometric proofs, it can mean that a statement is important. In algebra, it can mean multiplication.

...The asterisk symbol,*, is used in mathematics as an instruction to perform multiplication.

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