Setting Branding Options in Publishing Sites
People either love or hate the branding and look-and-feel of SharePoint out-of-the-box. Many people, particularly those who are using SharePoint for public-facing Internet sites, extensively redesign the interface; others don't change the interface. I don't recommend extensive changes to SharePoint sites for internal use. In my experience, intranet users are happy with the out-of-the-box styling. However, SharePoint does provide you with many ways to brand sites to meet the highest standards on the Web, and many SharePoint sites have been rebranded so much you cannot recognize them as SharePoint.
Core to the development of branding a SharePoint site is the master page. A master page looks after things like navigation (global and context) and the general look and feel of your sites. Master pages are used with page layouts, which manage the content of your pages. Master pages and page layouts are combined to produce most SharePoint pages on your site.
The actual content on your page, together with its look and feel, is controlled by another web authoring technology, Cascading Style Sheets (CSS). In SharePoint, a major CSS sheet is the corev4.css file, which is applied to almost every site you create — unless of course you override it with your own CSS file or override individual CSS styles! SharePoint CSS files can range in size from thousands of lines to only a few styles.
When branding SharePoint, it is important ...