Can any body tell me about the function of a boot loader and how to write the code .

I have a 89c51rd2 kit from SPJ systems with a cross compiler. I a doing simple programs with LCD, Serial port, Seven segment display , stepper motor and all .

After I am confident i am supposed to develop a test jig with 89C51RD2. But my problem now is that I am confident in wrriting the code for the test jig and designing the hardware for it,but after wrriting the code how to down load the code to the 89c51rd2 so that when it is powered on automatically my program takes the control over the test jig. I am not getting any information about boot loader.

Also my development kit has ISP facility .

Can any body help me explaining what should i do or where can I find more deialed information.

I am planning to write the code with C, since i have a cross compiler.

Awaiting reply .
LAL