JavaScript has both numeric and string types, and it converts between these as it encounters them in the script. It uses “+” for both numeric addition as well as string concatenation. Normally when you multiply the variables, it converts them to numbers and multiplies them. However, when you add them, it doesn’t convert the variables, but instead concatenates them. To convert the variables to numbers quickly is to multiply them by 1.For example:
var x = “1”; // This is a string
var xx = x + x; // This will be “11”
var y = “1”; // This is a string
var yy =( y*1)+( y*1); // // Now y is converted to a number when multiplied by 1. Here yy is 2