What Is Graphic Design (2014-2015)

As a senior in high school I have been involved with the e-Communication program for 4 years. I have held the focus of graphic design for 2 years, now I am trying to pursue a career in the field. Which of course I now have to know the answer to the question "What is graphic design?"
Graphic design is using shapes, images, and type to create an image which will portray a message. Right now I am employed as a t-shirt designer so I am using minimal shapes and type in order to display a message of an event or a cause. Being a t-shirt designer has allowed me to better answer the question and understanding of "what is graphic design?".  In order to create a message of an event I have to be wise in the amount and size of shapes and type. In t-shirt designs you can't make this extravagant image and then print it on a t-shirt, you have to constrain the design and get the message across in the simplest most understanding way. I hope throughout my senior year and my college career I will fully understand and impact the graphic design world. "In graphic design you have to do what is smart, right, and interesting."