内存驻留程序的基本思想就是让程序一直停留在内存中，不断的执行特定的命令。但内存驻留如何被执行呢？一般地，内存驻留程序都是通过修改BIOS或DOS的系统中断向量表来实现的。比如修改向量表中16H位置的中断（这个中断接收键盘的按键，在DOS中，按键按下，这个中断就会被调用），让其指向我的程序，这时若有按键被按下，则执行的是我的程序。-The basic idea is to let procedure has to remain in the memory and keeps the implementation of specific orders. But the presence of memory how to be executed? Generally, the memory presence procedures are revised BIOS or DOS systems to scale interruption to achieve. For example, changes to the set-16H location of the interrupt (the keyboard interrupt reception of keys, DOS, press the button, the suspension will be called), let me point to the procedure, if time was pressing the button, I was the implementation of the procedures.