JS中这句话怎么理解

Question

html

<ul id = "user-list">

  <li>张三</li>

  <li>李四</li>

  <li>王五</li>

  <li>赵六</li>

</ul>

js

let list = document.querySelector("#user-list")

let items = document.querySelectorAll("#user-list > li")

list.addEventListener('click', function(e) {

    if(e.target.tagName === "LI") {  //请问这2行怎么理解？

      let item = e.target

    

    items.forEach(function(item) {

        item.style.background = "inherit"

      item.style.color = "inherit"

    })

    

    item.style.background = "black"

    item.style.color = "white"

    

    console.log(item.innerHTML)

  }

})