Overlapping instructions were used in some 8 bit microcomputers to fit code into a small memory. For instance, Apple II cards have a 256 byte window for a tiny I&#x2F;O driver (the address of that window being slot-position-dependent, so the code has to be relocatable: plug the hardware into a different slot and the code moves.) Some cards use overlapping instructions in order to fit this constraint. (Cards can also provide a 2048 byte ROM. However, that was mapped to a fixed memory location shared by all the slots. Before anything jumps there, it has to ensure that the correct slot&#x27;s code is currently selected for visibility.)<p>Interestingly, in nature there are some viruses which similarly have overlapping sequences in their DNA.  That is to say, one entry point codes for a protein and then another entry point codes for another, and the sequences overlap.