VGA output requires a digital to analog converter (DAC): it can be done by three 270 Ohm resistors to have 8 colors, or by 6 resistors to have 64 colors.
Three fixed width fonts are embedded to best represents 80x25 or 132x25 text screen, at 640x350 resolution. However other fonts are embedded, even with variable width.
Sprites can have up to 64 colors (RGB, 2 bits per channel + transparency). Unlimited number of sprites are supported. However big sprites and a large amount of them reduces the frame rate and could generate flickering.
There is a graphical user interface (GUI) with overlapping windows and mouse handling and a lot of widgets (buttons, editboxes, checkboxes, comboboxes, listboxes, etc..).
Finally, there is a sound engine, with multiple channels mixed to a mono output. Each channel can generate sine waveforms, square, etc... or custom sampled data.