Why use symbol & when using scanf in C?

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The use of the ampersand symbol "&" in the C programming language's scanf function is essential for passing the address of a variable, such as in scanf("%d", &x). This is necessary because scanf requires a pointer to the variable to store the input value directly into it, allowing for modification of the variable's value. In contrast, printf does not require the address operator because it only needs to access the value of the variable without altering it.

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Why use symbol "&" when using scanf in C?

When using scanf like in scanf("%d",&x); why do we use '&' before x? can't we write directly ,x as in printf command? Is it just a convention? I think it should have a reason.. they won't just put an "&" just like that
 
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"&x" means to generate a pointer to "x". Scanf needs a pointer to x in order to store the value and change "x". Printf uses a copy of the value of "x" passed as a parameter (usually on the stack), since it isn't changing the value of "x".
 

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