side by side <div> and site centering - css

Question

I'm trying to convert my site from using tables to just using css and divs but I'm running into a lot of problems with trying to figure how to exactly do it, I've been looking for tutorials on centering a site with css and how to put divs side by side but I can't really find one that does both and I keep getting confused by how to exactly achieve this, I asked around a bit and I got told to use absolute positioning but still I can't really wrap my head around this.
So basically how would I arrange the 2 central div side by side while keeping the whole thing centered in the browser? The following image is the layout I'm trying to achieve:
the blue boxes are eventual other stuff I might want to put in them, such as a blog requiring again the use of side by side divs.
right now I have the following layout:
<div id="wrap">
<div id="banner"> banner </div>
<div id="navbar"> navigation links </div>
<div id="body"> stuff </div>
<div id="footer"> stuff </div>
</div>

Answer 1

General idea: http://jsfiddle.net/JjbJE/
A little specific but provide you a great adventure to learn HTML | CSS : http://jsfiddle.net/JjbJE/3/
float:left|right this property does the side by side trick
clear:both this property clear away the float property
Other things are pretty easy to learn, just head to W3Schools

Answer 2

First you need a main container to center everything. Then two separate divs. See the HTML below:
<div id="main">
<div class="box">Left Box</div>
<div class="box">Right Box</div>
<div class="clear"></div>
</div>
Here is the CSS you will need:
#main{
width:960px;
margin:0 auto;
}
.box{
width:450px;
float:left;
border:solid 1px #000000;
}
.clear{
clear:both;
}
Hope that helps.

Answer 3

Here's my general overview on converting to a CSS based layout - if you have a table based layout, this is a good plan - in the end you can do more, Google will like you more, and it's much cooler.
My strategy is to look at all the groups of things on your page. Whatever needs to go into a group together, put inside a div. Assign this div a class and/or id to style it. If the divs are grouped, put them together in a div too.
In your case, you have two chunks of content to group inside of divs. Style them to be the size and shape you like, background, border, whatever is needed. Then group them together in an additional div, and center it. This and the rest of the page content can go inside a container div, which will determine the width of the page, how it's aligned, etc.

Answer 4

One possibility is to have a centered wrapper class and contain the divisons inside of that:
<div class="wrapper">
<header></header>
<div id="middle">
<div class="main-article clearfix"></div>
<aside></aside>
</div>
<footer></footer>
</div>
Then to style, center the wrapper, float the aside and main-article:
.wrapper { width: 1024px; margin: 0 auto; /* the auto centers it */ }
header, footer, aside, { display: block; }
.main-article { width: 50%; float: right; }
aside { width: 50%; float: left; }
.clearfix:before, .clearfix:after { content: ""; display: table; }
.clearfix:after { clear: both; }
.clearfix { *zoom: 1; }
Note: This is untested, and uses the clearfix from the HTML5 Boilerplate.
Update 01.22.2014: This "Holy Grail Layout" has ben solved by Flexbox. Check out Solved By Flexbox for more information on recreating this layout (and many more).