Final answer:
After POST, the boot process continues with the system searching for the Master Boot Record or UEFI, which contains the bootloader that starts the operating system.
Step-by-step explanation:
After the Power-On Self Test (POST), the next step in the boot process for a tablet with Windows 8 installed is loading the operating system. Specifically, the system will look for the Master Boot Record (MBR) or Unified Extensible Firmware Interface (UEFI) firmware, depending on the system's firmware interface, where the bootloader is located. The bootloader is responsible for starting the operating system. Once the bootloader is found, it initiates the loading of the operating system kernel which eventually leads to the initialization of the system and the user interface becomes available for the manager to log in and access the system.