Sure! Here is an SEO-friendly HTML answer for the interview question:

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The Difference Between ID and Class Selectors in CSS

When writing CSS, it is important to understand the difference between ID and class selectors. The main distinction is that an ID selector is used to target a single unique element, while a class selector is used to target multiple elements.

Example Use Cases:

Using ID Selectors: ID selectors are denoted by a hash (#) symbol and should be unique within a page. They are typically used when styling a specific element that occurs only once on a page. For example, if you have a navigation bar that you want to style uniquely, you can use an ID selector:

<nav id="main-nav">
    <ul>
        <li><a href="#">Home</a></li>
        <li><a href="#">About</a></li>
        <li><a href="#">Contact</a></li>
    </ul>
</nav>

Using Class Selectors: Class selectors are denoted by a dot (.) and can be used to target multiple elements that share the same class. They are useful for styling similar elements across a page. For example, if you have a set of buttons that you want to style consistently, you can use a class selector:

<button class="primary-button">Click Me</button>
<button class="primary-button">Submit</button>

By understanding when to use ID and class selectors in CSS, you can effectively style and structure your web pages.

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