Reversing a string is a common interview question for JavaScript developers. Here’s a detailed explanation, including the problem statement, various methods to solve it, and a brief discussion of their time and space complexities.

//string reverse  
Input: "bpthink"  
Output: "knihtpb"
Input: "JavaScript"  
Output: "tpircSavaJ"

In the Javascript we have a few methods to reverse a string

Method:1 Using Built-in Functions

function reverseString(str) {
    return str.split('').reverse().join('');
}

// Test the function
console.log(reverseString("bpthink")); // Output: "knihtpb"
console.log(reverseString("JavaScript")); // Output: "tpircSavaJ"
[/code]//built-in functions 

function reverseString(str) {
    return str.split('').reverse().join('');
}

// Test the function
console.log(reverseString("bpthink")); // Output: "knihtpb"
console.log(reverseString("JavaScript")); // Output: "tpircSavaJ"

Code Breakdown:

1. Convert the string to an array: Use the .split('') method to split the string into an array of characters.
2. Reverse the array: Use the .reverse() method to reverse the order of the elements in the array.
3. Join the array back into a string: Use the .join('') method to combine the elements of the array back into a string.

Method:2 Using a For Loop

//Using For Loop 

function reverseString(str) {
    let reversed = '';
    for (let i = str.length - 1; i >= 0; i--) {
        reversed += str[i];
    }
    return reversed;
}

// Test the function
console.log(reverseString("bpthink")); // Output: "knihtpb"
console.log(reverseString("JavaScript")); // Output: "tpircSavaJ"

Code Breakdown:

1. Initialize an empty string.
2. Loop through the input string from the last character to the first character.
3. Append each character to the new string.