JS Common

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        onchange();
        onclick();
        onmouseover();
        onmouseout();
        onkeydown();
        onload();

                            
        Math.round(x)	Returns x rounded to its nearest integer             -14.51=-15  OR  -14.49=-14  OR  14.51=15
        Math.ceil(x)	Returns x rounded up to its nearest integer
        Math.floor(x)	Returns x rounded down to its nearest integer
        Math.trunc(x)	Remove decimal part                                  -14.4=-14
        Math.abs(x)     Returns the absolute (positive) value of x:          -14.4=14.4
        Math.random()   Returns a random number between 0 (inclusive), and 1 (exclusive):
                        to getrandom no. between 1 & 100000 Math.random(Math.random()x1000000)
                        to getrandom no. between 1 & 100000 Math.floor(Math.random()x1000000)

      Operator	               Description	              Comparing
        ==	                equal to                   x == 8     (False)
                                                           x == 5     (True)
                                                           x == "5"   (True)

        ===	          equal to & equal type            x === 5    (True)
                                                           x === "5"  (False)