[javascript] What's "this" in JavaScript onclick?

keyword this in addEventListener event

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function getValue(o) {_x000D_
  alert(o.innerHTML);_x000D_
}_x000D_
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function hide(current) {_x000D_
  current.setAttribute("style", "display: none");_x000D_
}_x000D_
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var bullet = document.querySelectorAll(".bullet");_x000D_
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for (var x in bullet) { _x000D_
  bullet[x].onclick = function() {_x000D_
    hide(this);_x000D_
  };_x000D_
};_x000D_
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/* Using dynamic DOM Event */_x000D_
document.querySelector("#li").addEventListener("click", function() {_x000D_
  getValue(this); /* this = document.querySelector("#li") Object */_x000D_
});
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li {_x000D_
  cursor: pointer;_x000D_
}
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<ul>_x000D_
  <li onclick="getValue(this);">A</li>_x000D_
  <li id="li" >B</li>_x000D_
  <hr />_x000D_
  <li class="bullet" >1</li>_x000D_
  <li class="bullet" >2</li>_x000D_
  <li class="bullet" >3</li>_x000D_
  <li class="bullet" >4</li>_x000D_
</ul>
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