function getTokens(rawString) {
  // NB: `.filter(Boolean)` removes any falsy items from an array
  return rawString.toLowerCase().split(/[ ,!.";:-]+/).filter(Boolean).sort(); // This is a return statement signifying to retuern rawstring in lower case and split the string into an array of substrings, and returns the new array. Make a new one that contains only items that a filtering function returns true. Sort the original array and make a new copy.
}

function mostFrequentWord(text) {
  // A function mostFrequentWord is declared
  let words = getTokens(text);
  let wordFrequencies = {};
  // this is signifying to let wordfrequencies = the value based on the conditional satement.
  for (let i = 0; i <= words.length; i++) {
    if (words[i] in wordFrequencies) {
      wordFrequencies[words[i]]++;
    } else {
      wordFrequencies[words[i]] = 1;
    }
  }
  //The code above will log the numbers 1 to 0 to the console. It says beginning at i= 0, log the value of i. After logging i, if i is less than or equal to the value of words.length, increment i by one, and then repeat the process.
  let currentMaxKey = Object.keys(wordFrequencies)[0];
  //let current MaxKey = the object in the word frequencies.
  let currentMaxCount = wordFrequencies[currentMaxKey];

  for (let word in wordFrequencies) {
    if (wordFrequencies[word] > currentMaxCount) {
      //If the word in wordFrequencies is greater than the currentMaxCount return the currentMaxKey.
      currentMaxKey = word;
      currentMaxCount = wordFrequencies[word];
    }
  }
  return currentMaxKey;

}