If by material you mean chemical element, then silicon is the material. Its a group IV metal on the Periodic Table and is a semiconductor. It is also the second most abundant material on earth, with roughly 25 percent of the earths crust being some sort of silicon compound, (oxides and such)
Semiconductors' electrical resistance can be controlled by adding impurities from group III and group V elements from the periodic table. This allows precise control of electrical characteristics from which useful devices such as the Transistor (electrical switch) can be made from.
Switches can either be ON or OFF. This is represented in the computer world as 1 or 0. By combining these electrical switches useful information can be stored in terms of 1s and 0s. A 1 or 0 is called a Bit; a string of eight 1s or 0s is called a byte.
Hope this helps...
There are 2 physical components of a computer.
Software and Hardware. For great example of each go to:
http://www.slideshare.net/Amitchandra.5681/components-of-computer-2-presentation
Inside the HDD the data is stored in circular discs called Platters.This is made of Aluminium Substrate or Glass Substrate.
The coating of magnetisable "paint" on the surface of aluminium disks inside the drive mechanism.
Storage Medium
Hardisk
PLATTER
Hardware
binary
Hardware
Memory cache stores frequently used instructions and data on a computer. Cache memory is stored on a memory chip in an area of the RAM.
The computer's Random Access Memory (RAM) temporarily stores data and programs while your computer is on.
RAM
data sher
Upgrades infer that you upgrade the physical components of the computer,rather than any of the data inside it's storage devices.
a section of ram where the computer stores copied data
A computer.
The CPU
Hardware
It stores the data that's on your computer.
The server.
It uses hardware.
Representation of data refers to the way information is structured and displayed in a format that can be easily understood and processed by machines or humans. This can include using tables, charts, graphs, or other visual aids to present data in a meaningful way for analysis and decision-making.
If your question is whether registry is physical in computer processor, the answer is no.