New querySelector() and querySelectorAll()

Catching up with JavaScript after years of using jQuery I found these two shortcuts for replacing longer getElementById() methods. NOTE: the querySelector is passed an ID in the CSS format

<button id="our-button">Add New Item</button>

<script>
    // These are both the same
    var ourButton = document.getElementById("our-button");
    var ourButton = document.querySelector("#our-button");
</script>

<ul id="our-list>
    <li>A thing</li>
    <li>Another thing</li>
    <li>A new thing</li>
</ul>


<script>
// These are both the same
   var listItems = document.getElementById('#our-list').getElementsByTagName("li");
   var listItems = document.querySelectorAll("#our-list li");
</script>