JavaScript Implict Conversion to String

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Implicit conversion is when JavaScript automatically converts one data type to another. 

let str;

str = '1' + 2; 
console.log(str) // "12"

str = '1' + true; 
console.log(str); // "1true"

str = '1' + undefined; 
console.log(str); // "1undefined"

str = '1' + null; 
console.log(str); // "1null"

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