Input, Output And Storage Flashcards
What are input devices?
Allow interactions with a computing systems
What are examples of input devices?
- QR codes
Link to websites - 3D scanners
Measure and compare the proportion proportion of persons face with those stored
Tech = tomography - 2D scanners
- Sensors
What are output devices?
Take data from computer and turn it into human readable form.
What is RAM?
- Random Access Memory
- data currently stored in memory
- power off = data lost
- read and write
- operating system
What is ROM?
- read only memory
- read only
- computing boot up instructions (bootstrap)
- power off and memory retained
- data stored in files
What is virtual memory?
Part of hard drive use as extension from RAM.
What is primary storage?
Volatile meaning the data is lost
What is secondary storage?
Non-volatile meaning the data is not lost
What does the RAM contain?
- OS
- software in current use
- data software being used
- turned off = RAM empty
- application and programs loaded copy into RAM from secondary storage
What is RAID?
- Most common technologies
- used with both HDD and SSD
- multiple drives come together to perform one single drive
What is RAID0?
STRIPED
- provide improved performance and additional storage
- NOT provide fault tolerance
- any errors on disc destroy RAID array
What is RAID1?
- disc provide same info
- provide some fault tolerance
- data is repeated
Read time increase
Write speed decrease
What is RAID 3-4?
Striped parity
- requires 3 discs in arrays
- provide parity checks and error connection and fault tolerance
- parity info stored on SINGLE DRIVE = other drives work when 1 fails
- lost data can be calculated using parity data stored on parity drive
What is SAN?
STORAGE AREA NETWORK
- connect numerous different types of storage devices as single device
What is Virtual Storage?
SAN and related techs are complex, offer extra layer on top to hide their complexity
Offer key services
1. Backup
2. Archiving
Administration done thro central server
What is magnetic storage?
- reliable
- cost effective
- high capacity
What is optical storage?
- slow transfer speed
- low cost
- robust
- distribute video or progs
What is solid state?
- portable
- capacity is increasing
- sectors may become unusable
- quality deteriorates in cheaper flash devices
What is an OS?
Group of programs manage interactions between humans and hardware
What does the OS provide?
- user interface
- memory management
- peripheral management
- multi tasking
- user and file management
What are the different types of OS?
- Linux
- macOS
- android
- windows
