You can use the float command in your css file:
Code:
CSS
.images {clear:both; margin:2em 1em}
.floater {float:left; width:20%; margin:0}
HTML
<div class="images">
<img class="floater" alt="" src="../Images/img_1.png"/>
<img class="floater" alt="" src="../Images/img_2.png"/>
<img class="floater" alt="" src="../Images/img_3.png"/>
<img class="floater" alt="" src="../Images/img_4.png"/>
</div>
-OR-
Code:
CSS
.images {clear:both; margin:2em 1em}
.images img {float:left; width:20%; margin:0}
HTML
<div class="images">
<img alt="" src="../Images/img_1.png"/>
<img alt="" src="../Images/img_2.png"/>
<img alt="" src="../Images/img_3.png"/>
<img alt="" src="../Images/img_4.png"/>
</div>
I prefer the 2nd one...it's a little cleaner.