Hello, I read that the Arduino UNO has a .5KB bootloader program in the memory. Is this bootloader important in the programming of the Arduino UNO or not? If I copied the Arduino UNO design and wanted to program it do I need a bootloader or not? If I don't need the bootloader would I be able to program my Arduino UNO copy design with the Arduino 1.0 IDE?
Thank You
If you don't have the bootloader, you would need an external 'device programmer' like an AVRASP to program sketches. In theory, this would still be possible from the IDE; you may need to adjust some config files or menus to tell it what kind of progammer you are using, and use the "upload using programmer" command instead of just the upload button.
The bootloader is not involved in the actual execution of sketches, so it need not be present in the chip for sketches to operate properly. The bootloader is only used for uploading to the chip.