Computer Science - Memory and Storage Part 1 Flashcards
What does RAM stand for?
Random Access Memory
What is RAM?
The main memory in a computer, which can be read and written to
Is RAM volatile or non-volatile?
Volatile
What does RAM store?
Data, files and programs currently in use
What does ROM stand for?
Read Only Memory
Is ROM volatile or non-volatile?
Non-volatile
What does ROM come on?
A small factory-made chip built into the motherboard
What does ROM store?
The instructions needed to boot (BIOS)
What is volatile memory?
Temporary memory which requires power to retain its data
What is non-volatile memory?
Permanent memory which keeps data even when the power is off
When is virtual memory created?
When RAM is full/running slowly
How is virtual memory created?
The operating system moves data from RAM to a location on secondary storage (virtual memory). The data can be swapped back to RAM if needed
What is primary storage?
Memory which is directly accessed by the CPU
Give 4 examples of primary storage:
ROM, RAM, Cache, Registers
Is secondary storage volatile or non-volatile?
Non-volatile
What does secondary storage store?
Data which is not in use (operating systems, applications, user files)
What does SSD stand for?
Solid State Drive
What are solid state storage devices?
Storage devices with no moving parts
Do SSDs have fast/slow read/write speeds?
Fast
What are solid state storage devices?
Storage devices with no moving parts
Give 2 examples of Solid State storage:
Any 2 from:
SD card
USB stick
SSD internal/external drive
Give 2 examples of optical storage:
Any 2 from:
CD, DVD, Blu-Ray
Advantages of optical storage?
Very portable, cheap per GB
Give 2 examples of magnetic storage:
Any 2 from:
Hard drives, magnetic tape, Floppy disk drive
Advantages of magnetic storage?
Large storage capacity, low cost per GB
What is the capacity of a device?
Amount of data that can be stored on a device
What is the speed of a device?
How quickly can the data be accessed from or written to the media
What is the reliability of a device?
The shelf-life of the media. How long it will retain data so that it can be accessed reliably and without error in the format it was originally saved
What is the portability of a device?
How easily it can be moved about. This depends on the size and weight of the media
What is the cost of a device?
How expensive the media is in terms of cost per GB of storage
What is the durability of a device?
How resistant the media is to damage - whether it’s rugged enough to survive rocks, scratches, etc.
What is a bit?
A single binary digit (1 or 0)
What is a nibble?
4 bits or half a byte
What is a byte?
8 bits
How much can one byte hold?
One typed character
What is a kilobyte?
1000 bytes
How much can one kilobyte hold?
About 2 pages of text
What is a megabyte?
1000 kilobytes
How much can one megabyte hold?
1 minute of mp3 audio
How much can two megabytes hold?
A high quality digital image
What is a gigabyte?
1000 megabytes
How much can 4-8 GB hold?
A DVD movie
What is a terabyte?
1000 gigabytes
How much could 1 terabyte store?
250 films or 250000 photos
What is a petabyte?
1000 terabytes
How much can a petabyte store?
11000 movies or 4000 photos per day for a lifetime
How much storage does YouTube have?
400PB
