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Storage devices (RAM and ROM (ROM (read only memory) stores the bootstrap…
Storage devices
RAM and ROM
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RAM (random access memory) is known as the computers 'working memory' because it is used for temporarily storing data and running programmes that computer is working on and the operating system 
The architecture: :classical_building:RAM is volatile. This means its contents and data can be changes but is lost when the computer is switched off. SO YOU CAN READ AND WRITE DATA! RAM is made up of series of chips known as the illustrator and modules that make your applications actually work. RAM can also multitask and switch between windows that are open.
ROM (read only memory) stores the bootstrap (computer bootup) instructions/ the instructions used to load the operating system when the computer is switched on.
The architecture: :classical_building: ROM is a form of permanent, non volatile storage and data is not lost when you witch the system off. The data can only be read and not edited. The ROM chip is matched to the motherboard and it contains details of the CPU it is using.
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Virtual memory
Virtual memory is used when there is not enough space on the RAM to hold all programmes simultaneously, so some of the hard disk has to be used (this is called virtual memory).
The advantages of virtual storage are that the size of program can be more than the size main memory so memory can be used efficiently. Furthermore, virtual memory allows sharing of code and data and reduces internal fragmentation.
The disadvantage for virtual storage is that it increases overhead for handling paging interrupts, software complexity and hardware costs.
Secondary Storage Allow for back-ups to be made and avoid the user form re-entering data and programmes by storing it on a permanent, non volatile copy.
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Magnetic Storage
An example of magnetic storage is a hard disk. These are used a lot in computing since they have high data transfer rates and high storage capacities of 500 gigabytes - 10 terabytes.
Architecture: Several metal disks which have concentric tracks are mounted onto the same spindle in a sealed unit and connected to a power supply inside the computer. The disk can spin at a high speed of 3,600 to 7,200 rpm and spinning platters are read by drive heads.
Optical Storage
Architecture: Binary data is burned onto hard plastic disks with mirrored surfaces creating a set of pits and lands using a laser beam. The pit represents a binary 0 and the lands represent 1. Laser beams are then used to read it by reflecting lights at different amounts which can be picked up and decoded.
Optical disks are cheap but need to be handled with care as scratching the shiny side causes it to become inoperative. Optical disks also have a slow transfer rate than hard disks or SSD devices.
Software mailing is best suited for optical disks, it is cheap to manufacture and distribute and robust and lightweight.
Virtual Storage
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Advantages: The cloud provider maintains the data storage size (so you can increase or decrease the storage).
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