所有的PC系统都是通过执行rom(明确地说，BIOS)中的代码从引导磁盘的0柱面0扇区加载扇区，从而开始引导过程。

All PC systems start the boot process by executing code in ROM (specifically, the BIOS) to load the sector from sector 0, cylinder 0 of the boot drive.

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如果这个磁盘是可启动的，那么第一个扇区被称为启动扇区，因为这是启动引导代码存在的地方。

If the disk is bootable, the first sector is called the boot sector, since this is where the boot loader code resides.

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