My first useful program I ever wrote was a font editor.

To load into a terminal program that emulated a real terminal that loaded fonts.

I supported the terminal program. I was NOT a programmer yet. I was assigned to create the font maps by hand, by charting them on paper, then typing x/y coordinates into a data file.

I was learning C at that point. I taught myself enough curses and Unix to create a full screen bitmap editor to avoid the task.