The next required skill is basic hardware knowledge, computer hardware consist of the physical parts
of a computer like the central processing unit.
You monitor mouse, keyboard, computer, data storage, graphics card, sound cards, speaker and motherboard,
etc..
By contrast, the software is designed to of instruction that can be stored and run by a hardware.
For example, suppose you want to hack a machine that is controlled by a computer.
Firstly, you need to know about the machine or how it's work, correct.
You have to get the access to the computer that controls the machine.
Now, the machine will have a very good software security system.
However, hackers don't care about hardware security, so if you so you can play with the hardware,
if you can access it.
If you don't know about hardware, then how will you know how Motherboard works, how you wish to transfer
data, how bias works, etc., So you must have basic hardware knowledge also to become a great ethical
hacker.