Confusing web design with web development is an all too common mistake that people make if they are not familiar with the industry; but a designer and developer have very different roles.

Web Design is the most common term used. A “web designer” refers to a very broad set of skills, one of which is visual design.
The “design” part deals with the customer-facing or “front end” part of the website.

A web designer focuses on how a site looks and how the customers interact with it. Good web designers use the principles of design to create a great looking site. It involves every aspect of how the site appears and functions, taking into account the principles of good visual design as well as a deep understanding of user experience and the client’s needs. A good web designer makes a site look great and work well for the site user. Sometimes a web designer will write mark-up code for the website such as in HTML, CSS, and XML.

Web development refers to writing the actual programming or logic code and scripts that take a web design into a functional working website. It’s the “how” behind the “what” of a design.
Developers focus on how a site works, what actions can be performed on the site, and how to make all the invisible things (that happen behind the scenes on websites) actually work.

Web development comes in two parts; the front-end development and back-end development. Some of the skills overlap, but they do have very different purposes during the web design process.

A front-end developer takes the visual design of a website (whether they created that design or it was handed to them by a visual designer) and builds it in code. A front-end developer will use HTML for the structure of the site, CSS to dictate the visual styles and layout, and perhaps even some Javascript. For some small sites, front-end development may be the only kind of development that is needed for that project. For more complex projects, “back-end” development will come into play.

Back-end development deals with the more advanced programming and interactions on the pages. A back-end web developer focuses on how a site works and how the customers get things done on it using certainly functionality. This could include working with code that interfaces with database or creating features like Ecommerce shopping carts that connect to online payment processors and more.

Good web developers may know how to program scripts like PHP or ASP.NET. They will also understand about how web forms work and how different software packages and API (application programming interfaces) can be used to connect those different packages.

Ultimately, when you are looking for a professional to work on your site, you need to consider whether you require a web designer or web developer.