A T-shirt is a style of shirt. A T-shirt is buttonless and collarless, usually with short sleeves and frequently a round neck line. T-shirts can be decorated with text and/or pictures, and they are often used to advertise, promoting products, companies, films and websites.

Vector graphics is the use of polygons to represent images in computer graphics. wikipedia.org

Print design is the process of creating and formatting projects using layout software that is ready to be printed by the end user. It is especially helpful when multiple persons or agencies are working on the same project. wikipedia.org

Computer illustration or digital illustration is the use of digital tools to produce images under the direct manipulation of the artist, usually through a pointing device such as a tablet or a mouse. wikipedia.org