Dreamweaver is a WYSIWYG program or What you See is What you get. Unlike notepad you can work directly on the website and see an image of it and edit the image itself in dreamweaver to see exactly what it looks like. Dreawmweaver is best used in couple with Fireworks since you can slice and make buttons and stuff in fireworks. So you can make a whole template in PS, slice it and add buttons and stuff in fireworks, export it, than open it in dreamweaver and do all the HTML or any other code u want.