You can add as many harddrives as you want to. As long as there is enough room.
Most are installed inside the computer. Depending on which type of computer you have (Desktop, Tower, Laptop) it may or may not be easily accessible.
Firewall is not a physical object in a computer, it's part of the software installed on your hard drive.
Yes, the motherboard does determine what hard drive can be installed. A computer is made for the hard drive to be compatible with whatever mother board is installed.
The drive that the OS is installed on
Hardware is the physical parts that are connect inside your computer. Hardware Devices are the hardware drivers installed on your hard drive.
There is no hard drive recovery software installed on my computer. Most computers will require this software to be installed by the user. There are many options available for hard drive recovery software.
hard drive
... and a storage device, usually the Hard Disk Drive. This way you can have more "available" memory than physical memory installed on your computer.
Usually Windows is installed on the C:/ drive of your compuer. Press WINLOGO+E to see your hard drives
Usually it is installed on your HDD (Hard Disk Drive).
Format hard drive/s
hard drive