- ID is an unique selector
- Same ID name shouldn't be used on another element
- An element can have only one ID attribute
- ID has more specificity than a
class
attribute
Example: index.html
<!-- BAD -->
<body id="main-container">
<div id="main-container"></div>
</body>
<!-- GOOD -->
<body>
<div id="main-container"></div>
</body>
- Same Class can be used on more than one element
- An element can have multiple Classes
Example: index.html
.none {
display: none;
}
.list {
padding-left: 10px;
}
<!-- Same class on multiple elements -->
<div id="main-container" class="none">I am DIV element</div>
<span class="none">I am SPAN element</span>
<!-- Multiple classes on multiple elements -->
<ul>
<li class="list none"></li>
<li class="list none"></li>
<li class="list none"></li>
<li class="list none"></li>
</ul>