Memory and Storage Part 1 Flashcards
What is RAM?
Random Access Memory is the main memory in a computer. It can be read and written to. RAM is volatile. RAM stores data, files and programs currently in use.
What is ROM?
Read Only Memory is non-volatile. Rom comes on a small factory- made chip built into the motherboard. It stores the instructions needed to boot (BIOS) and hardware settings.
Can ROM and RAM both be directly accesssed by the CPU?
Yes
Why is it called RANDOM Access Memory?
The memory addresses can be accessed in any order
Is the Hard Disk volatile or non-volatile?
Non-volatile
What is Volatile memory?
Volatile memory is temporary memory. It requires power to retain its data.
What is Non-volatile memory?
Non-volatile is permanent memory; it keeps data even when the power is off.
What is Primary Storage?
Primary storage refers to the memory that is directly accessed by the CPU e.g. ROM, RAM, Cache, Registers
What is the purpose of Primary Storage?
To hold both data and programs that are in current use by the CPU.
What is Secondary Storage?
Secondary storage is non-volatile. It is where all data (the operating system, applications and user files) are stored when not in use.
What is the purpose of Secondary Storage?
Without secondary storage all programs and data would be lost the moment the computer is switched off
What is Virtual Memory?
When RAM is full the operating system moves data from RAM to a location on secondary storage called Virtual Memory. The data is swapped back to RAM if needed.
Is Virtual Memory volatile or non-volatile?
Volatile
What moves the data from RAM to Virtual Memory?
Operating System
Why does the use of Virtual Memory cause slower processing?
Data that is not being used is swapped from Virtual Memory to RAM and this swapping process slows down the computer
What is meant by ‘Disk Thrashing’?
The hard drive is being overused due to data being swapped between RAM and Virtual Memory.
Why is Flash technology now being used instead of ROM?
Flash is non-volatile and also Read/Write
What are the three main types of secondary storage device?
Solid State Devices
Optical Devices
Magnetic Devices
What are Solid State Devices?
Solid State Drives (SSDs) are storage devices that use non-volatile random access memory (RAM) to store data indefinitely.
They have no moving parts and are more durable.
SSDs have fast read/write speeds.
Solid State storage includes SSD Internal / External drive, USB Stick, SD Card.
What are Optical Devices?
Optical devices use a laser to scan the surface of a spinning disc made from metal and plastic. It is very cheap per GB and is very portable.
Optical storage includes CDs, DVDs and Blu-ray.
What are Magnetic Devices?
Magnetic devices use magnetic fields to magnetise tiny individual sections of a metal spinning disk.
Magnetic storage includes hard drives and magnetic tape. Both of these have a large storage capacity and have a low cost per GB.
What are the factors that should be considered when choosing a form Secondary Storage?
Capacity
Speed
Portability
Reliability
Durability
Cost
What is Capacity?
The amount of data that can be
stored on the device.
What is Speed?
How quickly can the data be accessed from or written to the media.
