Creates a new string by joining two or more strings.
string.concat(string1, string2, …, stringN)
string1, string2, …, stringN: Strings to concatenate to the original string.
Here is an example of the function:
let str1 = "Hello";
let str2 = "World";
console.log(str1.concat(", ", str2)); // Output: "Hello, World"