When working with an HTML document that will be posted on the web, it is important to bring your attention on how you lay your HTML tags and how it its being used. For example, in your website, you post your web site name which is WEB STANDARD WEBSITE. So we have to use <H1> WEB STANDARD WEBSITE </H1>.
The old traditional way of marking up, we tend to use TABLE in laying out the structure of our webpage. Now they introduce DIV. Div is a markup for grouping and sorting website components that groups each website portion and function. Div is a block-level whereas a span is an inline element which can be seen and present in Adobe Dreamweaver.
Here is how it looks like in Dreamweaver:
Block and Inline element Display on Dreamweaver
Visually it looks like a whole block that group content.
So this is where CSS comes in to rescue, when you want your HTML tag to have a block element. #id { display : block; }