I want to make sure I understand this code correctly!

I'm just going to give an explanation of the code below to make sure I understand it correctly. If I am missing anything, can the community let me know please?

From top to bottom, the getRandomNumber function is producing a random number from 1 to 100 and storing that value within randomNumber. At the moment, guess has no value, so that when the while loop checks the condition, it evaluates to as true. The code block then runs, the guess variable is now given a value by utilizing the getRandomNumber function and the 1st attempt is recorded. The process is then repeated until the value given to guess is matched correctly with the randomNumber produced each time. That sounds right, correct?

var upper = 100;
var randomNumber = getRandomNumber(upper);
var guess;
var attempts = 0;

function getRandomNumber(upper) {
  return Math.floor(Math.random() * upper) + 1;
}

while ( guess !== randomNumber ) {
  guess = getRandomNumber(upper);
  attempts += 1;
}

document.write("<p>The random number was: " + randomNumber + ".</p>");
document.write("<p>It took the computer " + attempts + " attempts to get it right.</p>");