Young me remembers fondly poking and peeking system memory locations to see what happens. The manual, if I remember right, had a table of memory locations to system settings. Things like font and background colors.

I made a “punch out like” boxing game in basic where the background color blocks was the opponent and the font lines was your character via poking memory locations.

It was slow but I was just a kid at the time. It definitely told me what I wanted to do for a living at an early age.