What is the difference between a web developer and a web designer?

Just a quick overview to explain who does what :-)

What Exactly is a Web Designer?

The best Web Designers are of the creative type.  They have a knack for getting inside of their clients' heads and realizing their clients' vision.  They take this vision and masterfully convert it into an aesthetically pleasing, artistic Design that aims to impress millions of potential viewers.  Some designers study typography, user interface design, and usability.  Most include tools such as Photoshop, Illustrator, and DreamWeaver in their arsenal and frequent sites such as iStockPhoto, Kuler, and a long list of CSS galleries.

It is common, albeit arguable, that a designer's role should also include slicing images, writing (X)HTML, coding CSS, and drafting or editing copy.  For the most part, you can think of a Web Designer as a creative expert.

What Exactly is a Web Developer?

Web Developers are usually more technical in nature.  They tend to have excellent problem solving skills and are generally good at math.  On a daily basis, a developer will write code in five or more different languages including (X)HTML, CSS, JavaScript, [PHP, ASP, ColdFusion, Ruby, Python, Perl, etc.], and some flavor of SQL.  Web Developers can usually be found wielding some kind of text editor or IDE, an FTP client, three or more web browsers, and development plugins such as Firebug.  They frequent sites similar to the PHP manual, the Mozilla JavaScript reference, and the jQuery Documentation.  A developer also knows what an API is and how to develop with it.

Although Web Developers are sometimes referred to as programmers, their skills usually exceed those of a conventional software developer.  Think of a Web Developer as more of a technical expert with programming skills.

Source: ABeautifulSite.net