<img> tag within <a>: css behaviour and background

[mickey0]

Hello,
I'm trying to put these images in line without any spaces surround. I wrote this piece of code and I'd like to understand why that code has that behaviour. Why the the <img> is not within the <a> element??
Any good links to this point will be very appreciated. Thanks.
http://www.2shared.com/photo/sMP1mE2I/followus.html

#followus {
    clear: left;    
    float: right;
    width: 300px;
    background: pink;
    padding: 10px; margin:10px;
    border: Dashed 2px;     
}
#followus img {    
    border: Solid 2px;     
    padding: 5px;
    margin: 10px;
}
 
 
#followus img:hover {
    border: Solid 2px yellow; 
}
 
#followus a {
        /* display:inline */
    width: 70px;    
    border: Solid 2px yellow;                 
}
#followus a:hover {        
        background: black;        
}
 

<div id="followus">
 <a....> <img ..... /> </a>
 <a....> <img ..... /> </a>
</div>    
 

[zorgi]

Anchor tag is inline element. Width or height don't work on inline elements. Try setting:

#followus a {
.
.
.
display: block;
float: left;
}

However I would probably remove all styling on anchor tag and just play with padding on images.