Div Elements are typically block styled elements, but you can change them to display horizontally by setting the style attribute to inline-block or floating them left or right:
<div style="border:1px solid blue; margin: auto; height:250px; width:600px;">
<div style="display:inline-block; border:1px solid red; height:50px; width:80px;"></div>
<div style="display:inline-block; border:1px solid red; height:50px; width:80px;"></div>
<div style="display:inline-block; border:1px solid red; height:50px; width:80px;"></div>
<div style="display:inline-block; border:1px solid red; height:50px; width:80px;"></div>
</div>
OR:
<div style="border:1px solid blue; margin: auto; height:250px; width:600px;">
<div style="float:left; border:1px solid red; height:50px; width:80px;"></div>
<div style="float:left; border:1px solid red; height:50px; width:80px;"></div>
<div style="float:left; border:1px solid red; height:50px; width:80px;"></div>
<div style="float:left; border:1px solid red; height:50px; width:80px;"></div>
</div>