It depends there are two fields in the web area
You can do both but people tend to excel at one or the other but still have skills in the weaker area. Me for example am a web programmer but can still use Photoshop and other programs to design.
If you want to own a business in it then you need to learn the following. By the way you will need to know a bit out side of web as well.
PHP / ASP.net (One or the other preferably both.)
You also need to know about files
and so on like you can't use .gif images for big image displays as gif have very limited amount of colour were as JPG and PNG are suited to large images.
You also need to learn software such as
Dream Weaver (For professional use)
me personally I don't use dreamweaver but I can use it if you follow me learn yourself in Notepad ++
the reason being you will learn by mistake but at the end you will be smarter.
You also need to know about servers and general computer abilities.
and so on.
You have to know that peoples computer processing power may not be great and take this into consideration when building sites. Also understanding when you are building a site the number 1 error people make is making a site that they like this is wrong.
Make a site that people will like not you. Make it simple to use make it clear but not boring. Google for example it smain page contains no more than a couple of images and some links.
You don't have to learn all of the above just have an understanding.
If you need more help with anything just ask me.
if you want it http://notepad-plus-plus.org/download
wamp (server) http://www.wampserver.com/en/download.ph...