When we are talking about designing and developing, there are slight differences between these two terms in modern IT world considering tools that they use.
A web designer uses graphics and graphic design software ( Adobe Photoshop, Illustrator and InDesign) to create a look for web. This design is then proceeding to coding phase. The designer may not always be the person writing the code and in some cases work independently of the team who will take a website design live. Much of a designer’s job is creative and uses both intuition and imagination, often characteristics of people who are considered right – brained.
You can be designer and developer at the same time. More people are beginning to label themselves in this way and it is always better if you understand the logic of the opposite side and how it works.