SLR 3 Flashcards
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
Define storage device
Any device used for either temporary or permanent storage of data- can be internal or external
Input device example
Mouse
Keyboard
Microphone
Sensor
Touchpad
Remote control
Scanner
Camera/ webcam
Touchscreen
Barcode reader
Magnetic strip reader
Chip and pin
Joystick
Optical character recognition
Output device examples
Monitor,
Printer
Speaker
Headphone
Digital/ data projector
Plotter
Actuator
Touchscreen
Storage device examples
CD
DVD
Blu-ray
USB / flash drive
SD card
Portable solid state drive
Internal solid state drive
Magnetic hard drive
Mass storage tape
External hard drive
Cloud storage
