SLR 3 Flashcards
(28 cards)
Define drive
The device that reads and writes data from secondary storage
Define media
What the data is actually stored on
Define optical storage
Data is stored in the reflectivity (pits and lands) of a surface and is read and written to by a laser
Pros of optical storage
Cheap
Lightweight
Portable
Cons of optical storage
Slow access times
Prone to scratches
Define solid state/ flash drive
A solid state technology that stores data on a collection of memory chips. No moving parts as data is accessed by software
Pros of solid state/ flash drive
Durable
Fast access times
Cons of solid state/ flash drive
Cost
Limited read/ writes
Define magnetic storage
Relies on the polarisation of magnetic particles to store bits on a magnetic material which is typically moved mechanically. A high capacity and low cost means of storage
Pros of magnetic storage
Cheap
Large capacity
Cons of magnetic storage
Slow access times
Fragile
Examples of optical storage
CD-R/RW, DVDR/RW, Blu-ray
Examples of solid state
SSD, memory sticks, flash memory cards
Examples of magnetic
Hard disk drive, tape
ROM characteristic
Small pieces of read only memory located on the motherboard
Non-volatile
Contains very first instructions for the computer (bootstrap)
RAM characteristics
Temporary storage of instructions and data
Holds information being executed by the processor
Volatile
Much faster than the hard disk
How are RAM and ROM involved in computer system turning on
When a computer system first receives power, there are no instructions in the CPU.
The system needs to load the operating system so it can start functioning.
ROM contains the bootstrap, a set of initial startup instructions placed in the ROM during manufacturing.
The first initial instruction performs a power on self test (POST)
The POST sends signals to all connected components, wakes them up and makes the CPU aware of their existence.
As the computer is now aware of the hard drive, it can load the operating system into RAM. The process of booting up your operating system can now begin
What is virtual storage
The concept of storing and retrieving data over the internet in the cloud instead of a local storage device
Advantage of virtual storage
Data can be accessed at any time… from any device… as long as there is internet access
Data can be easily stored without the need for removable media transfer
Easy to collaborate
Storage considered to be limitless from the users point of view
Disadvantage of virtual storage
Can become expensive
If connectivity is poor, access times can be slow
No internet connection means no access to your files
Where is the data stored? (Virtual memory)
All of the data actually stays on physical, permanent storage media in a remote location
Example of virtual storage
On a computer you see a single storage area neatly structured and organised under a single drive- logical abstraction.
The physical implementation could have the folders, files and associated data stored across different media (magnetic hard disk, solid state disks, network file servers, cloud storage)
Define input device
Any device that allows you to pass information from the outside world into a computer system
Define output device
Any device that can take data stored in digital form and convert it into another format that humans can process such as sound, images or vibration
