2D graphics include everything we can display on the monitor or print on paper. ROOT needs to be interfaced with our operative system's graphics engine, in order to be able to display windows containing some plot, for example. ROOT uses the X11 graphics engine on unix-like systems and Win32 on Windows, but can also use the multi-platform Qt library by Trolltech (available also as open source).

One can save canvases into several possible formats. The best quality is obtained by means of vector graphics like PostScript or PDF (the usual choice for papers), but raster graphics is usually a better choice for images to be included in web pages.

Through the libAfterImage library, ROOT is also able to load bitmap images and to manipulate them.