The output will be 3. The expression 1 + + '2' may look confusing due to the double + signs, but here's how it's evaluated: The second + is the unary plus operator, which converts its operand to a number. So + '2' evaluates to 2 (the number). Then, 1 + 2 equals 3. The unary plus is often used as a shorthand for Number() to convert strings to numbers, analogous to how unary minus (-) can negate a value.