Primary Storage (RAM & ROM) Flashcards
What are examples of Primary Storage
RAM & ROM
What are examples of Secondary Storage
HDD (Hard Disk Drive) SSD (Solid State Drive) Offline secondary storage CD (Compact Disk) DVD (Digital Versatile Disc) Blu-ray USB Flash Memory Removable HDD Magnetic Tape
What does Solid State Media mean
Storage with no moving parts
Removable storage with no moving parts
Devices that use flash memory
Name characteristics of Secondary Storage
. Non-Volatile
. Programs and Data are stored on Hard Disk
. CD’s can be used to distribute software, music e-books etc.
. Memory sticks may be used to transport data from one place to another
. Magnetic Tape or External Hard Drives may be used for backup storage
What is Secondary Storage used for
Long-Term, Permanent, Non-Volatile Storage
Data is transferred from Secondary - RAM - Cache - CPU
Why is Secondary Storage Important
. Stores Data for long periods of time . Robust and Reliable . Much cheaper per MB than Main Memory . More capacity . Portable . Used to back up data stored in main memory/ primary storage . Stores programs/data that would be lost when power is switched off (Volatile) . Need for larger storage capacity
What are the 3 types of Optical Storage
Solid State, Optical, Magnetic
What is Optical Storage
Secondary Storage that uses lasers to read and write data on a reflective surface. Small in capacity but cheap to produce. Utilizes discs with a reflective surface to store data
What are the 3 Optical Disk formats
Read-Only
Write Once
Rewritable
Advantages of Optical Storage
Cheap for Small capacities
Very small and portable
last a long time
Disadvantages of optical Storage
Expensive for large capacities
Easily scratched
Slow read speeds
Limited reusability
What is Magnetic Storage
Secondary Storage that stores data in series as polarized dots.
Polarity of the dot (positive or negative) determines whether it stores a 1 or 0.
These devices come in very large capacities and are generally inexpensive.
Uses discs to store data, these platters are covered in a special material.
Sections of this material can be magnetized and demagnetized to represent data.
Read/ write head attached to an arm applies a magnetic field to specific sections to read / write
What are the two pieces of equipment Magnetic Storage uses
A set of discs (Platters)
An arm with a read/write head
How does magnetic storage write data
The platters spin and the read/write head will magnetize and demagnetize the sections underneath it
To read data the head moves over the spinning platters, measuring whether the sections are magnetized or not
Advantages of Magnetic Storage
Cheap for large capacities
Infinitely rewritable
Reliable for long periods of time
Faster read speeds than optical
Disadvantages of Magnetic Storage
Damaged if dropped or exposed to a magnetic field
Slower read speeds than solid state
Require a lot of power to run
How does Solid State work
Solid state storage has no moving parts, they store data inside electronic circuits which can be sat to a 0 or a 1. These devices are much smaller than magnetic devices. They have a large capacity but are more expensive. This type is also called flash memory. They are non-volatile
What are the characteristics of solid-state storage
No moving parts to read or write data A collection of circuits wired together to store binary data The collection of circuits are wired to form a grid Fast read and write speeds Still slower than RAM Is durable can withstand being dropped Is silent when running Require less power than other devices
Disadvantages of solid state
Expensive cost per MB
Typically a lower capacity than Hard Drives
Can be unreliable
Advantages of Solid State
Fast Lightweight Durable Low Power Silent
