Why is the W3C box model considered better? [closed]

Question

Why do most developers consider the W3C box model to be better than the box model used by Internet Explorer?

It's very frustrating developing pages that look the way you want them on Internet Explorer, but I find the W3C box model counterintuitive. For example, if margins, padding, and border were factored into the width, I could assign width values to all my columns without worrying about the number of columns, and any changes I make to their padding and margins.

With W3C's box model I have to worry about the number of columns I have, and develop something akin to a mathematical formula to calculate the correct width values when modifying margins and padding. Changing their values would be difficult, especially for complex layouts. Consider this small frame-work I wrote:

#content {
    margin:0 auto 30px auto;
    padding:0 30px 30px 30px;
    width: 900px;
}

    #content .column {
        float: left;
        margin:0 20px 20px 20px;
    }
    #content .first {
        margin-left: 0;
    }
    #content .last {
        margin-right: 0;
    }

        .width_1-4 {
            width: 195px;
        }
        .width_1-3 {
            width: 273px;
        }
        .width_1-2 {
            width: 430px;
        }
        .width_3-4 {
            width: 645px;
        }
        .width_1-1 {
            width: 900px;
        }

The values I assigned here will falter unless there are three columns, and thus margins at 0+20+20+20+20+0. It would be difficult to modify padding and margins; my entire widths would have to be recalculated. If column width incorporated padding and margins, all I would need to do is change the width and I have my layout. I'm less criticizing the box model and more hoping to understand why it's considered better as I'm finding it difficult to work with.

Am I doing this thing wrong? It just seems counterintuitive to use W3C's box model.

Answer 1

One word answer - -box-sizing

You choose how you want your box model to work.

Answer 2

Not everyone considers it to be better. To extract a quote from Quirksmode.

Personally I find W3C's box model counter-intuitive. To quote myself:

Logically, a box is measured from border to border. Take a physical box, any box. Put something in it that is distinctly smaller than the box. Ask anyone to measure the width of the box. He'll measure the distance between the sides of the box (the 'borders'). No one will think of measuring the content of the box.

Web designers who create boxes for holding content care about the visible width of the box, about the distance from border to border. The borders, and not the content, are the visual cues for the user of the site. Nobody is interested in the width of the content.

I agree, the border-box model makes more sense (at least, it does to me). There were disputes over the original W3C box model, leading to the definition of the box-sizing property in CSS3.

Answer 3

Personally, I prefer -to my occasional shame- IE's box-model. As noted by the OP it seems to make more sense to have a pre-defined width from which margin, padding and border-width are subtracted, than to have a width to which these are then added.

On the other hand, I can work with both models quite happily, all I really want is consistency between implementations, whichever implementation is chosen.