TI-83's had a restore function, where you could just restore all deleted programs. Not that we had to use them... to quote my gr.12 math teacher - "You're not a

TI-83's had a restore function, where you could just restore all deleted programs. Not that we had to use them... to quote my gr.12 math teacher - "You're not allowed to have programs on your graphing calculator, but they're not going to check, so you might as well." He wouldn't allow us to use the graphing calculator for his exams though, only the final.