How to make a paragraph reside within a div

Question

Text is going beyond the div. How can I enforce the paragraph that won't overflow outside the div ?

.preview {
    background: red;
    width: 200px;
}

<div class="preview">
    <p>aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa</p>
</div>

Answer 1

Use word-wrap:

.preview {
    background: red;
    width: 200px;
    word-wrap: break-word;
}

<div class="preview">
    <p>aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa</p>
</div>