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1 Answer

Steven Parker
Steven Parker
229,921 Points

The "+=" symbol is a special kind of assignment that adds a new string onto the end of the one already stored in the variable, instead of replacing it like "=" does. For example:

var words = "My ";
words += "car ";    // words now has "My car "
words += "is ";     // words now has "My car is "
words += "blue.";   // words now has "My car is blue."