main.js

var words = ["fun", "exciting", "about not giving up", "being helpful", "being open", "what I learned at CodingDojo!"],
  el = document.getElementById('magic'),
  word_counter = 0,
  character_counter = 0;

function updateText()
{
  var next_character = words[word_counter][character_counter++];
  if(next_character == ' '){
    next_character = ' ';
  }
  el.innerHTML = el.innerHTML+next_character;

  if(character_counter == words[word_counter].length + 1)
  {
    word_counter++; 	//choose a different word
    character_counter = 0;	//start over with the first character of the word
    el.innerHTML = '';  //set the html to be blank

    //if we're displaying the last word, go back to the first word
    if(word_counter == words.length)
      word_counter = 0;
  }
}

setInterval(updateText,250);