A vector image is one of two commonly used 2D graphic types. The other type is Bitmaps (also known as raster or pixel based graphic types). Vector graphics formats can sometimes be used with raster images. These are called metafiles.
Vector graphics are made up of many individual objects or geometrical primitives such as points, lines, curves and shapes. Each of these objects is defined by mathematical calculations and can be assigned properties like colours, fills, and outlines.
Computer software is generally use to create vector graphics. The most common vector programs include (Adobe Illustrator), (CorelDRAW), (Macromedia Freehand) or (Inkscape).
T-Shirt Printing is a good example where working with vector images is used as industry best practice. This is because Vector images are resolution independent, meaning they can be scaled indefinitely without loosing quality. Vector graphics also tend to have much smaller file sizes than raster-based bitmaps.

If you are unable to provide the artwork required by tshirtprinting.com.au please contact us or alternatively we operate our own artwork and design service that may be used if necessary.

Related:
General Requirements for T-shirt Printing
Artwork Requirements for T shirt Screen Printing
Artwork Requirements for Digital TShirt Printing