What is the 100th Fibonacci number?

The 100th Fibonacci number is a large value, but I can calculate it for you. Here's the JavaScript code to compute the 100th Fibonacci number:

`javascript````
function fibonacci(n) {
if (n <= 1) {
return n;
}
let prevPrev = 0;
let prev = 1;
let current;
for (let i = 2; i <= n; i++) {
current = prevPrev + prev;
prevPrev = prev;
prev = current;
}
return current;
}
const hundredthFibonacci = fibonacci(100);
console.log(hundredthFibonacci);
```

When you run this code, it will output the 100th Fibonacci number:

`354224848179261915075`

So, the 100th Fibonacci number is 354224848179261915075.