S3 Computer Systems, Binary, Cyber security Flashcards
Jan test revison
Examples of input devices?
Mouse, Keyboard
Examples of output devices
Headphones, monitor
Computer System diagram?
Input devices into Cpu
output dervices out of cpu
working memory both ways of cpu
backing storeage both ways.
Layout: Cpu in middle, Ram above, Backing storage below
input & output devices either side.
What happens when you open a file?
The file moves from backing storage to working memory and while working on file moves between cpu and working memory.
what happens when you save a file.
moves back into backing storage
What does it mean that the working memory is volitile?
It does not save when you turn off the computer
What does Cpu stand for?
Central Proccessing Unit
What does RAM stand for?
Random acess memory
What does GPU for?
Graphics proccessing unit
What does PSU stand for?
Power supply unit
What does SSD stand for?
Solid state drive
What does HDD stand for?
Hard disk drive
What does OS stand for?
operaiting system
What does the CPU do?
Brain of the computer, all the calculations are prefromed here.
What is the 3 things CPU is broken into?
Speed frequency(GHz)
Number of cores(1,2,4,8,ect)
Cache (1mb,4mb)
What does the RAM do?
Stores working data
Where does RAM solt into?
Mother board
What sizes does RAM come in?
4GB,8GB,16GB,64GB,128GB
What is the range of speed for RAM?
2133-4200MHz
What does the GPU do?
Produces a display so can use computer
Why is GPU useful?
Can create refection, transparency, shadows
Does the computer need GPU?
no
What is GPU measured in?
GHz
does it have a ram on board
yes
What does the motherboard do?
a device that connects all the components together so the computer can work
What must the motherboard match
CPU type
what connects to the motherboard
CPU,RAM,GPU,hard drive + extra compoents
What is the two things the PSU does?
Supplies the computer and components with the right power, changes the mains into a usable power supply
What is SSD & HDD
backing storage
3 things about HDD
Slower,More Fragile, moving parts
3 things about SSD
Faster, move expensive, longer life
What does the OS do?
It is a software responsible for making all the components speak to each other correctly
What does 1 and 0’s repersent and what are they?
a state of switch, 1 = on, 0 = off.
It is the smallest pieces of storage a computer can understand, know as a bit
what do 8 bits create
a byte
what does 1024 bytes equal?
1 Kilobyte
what does 1024 kilobytes equal?
1 megabyte
what does 1024 megabytes equal?
1 gigabyte
what does 1024 gigbyte equal?
1 tera byte
How do you find out the number of combos?
2 squared by the number of bits
what is ASCII?
a system to reperesent text
how many bits is the ASCII system
8 bit system
how many different characters is ASCII
256 different charactes
Why is ASCII not useful
it only has 256 character and there is more characters
what is UNICODE and why is it used
it is the alternaitve to ASCII and has more characters, 16 bit system
how many characters does UNICODE have?
65536
In a byte how do you find the number?
each 0/1 has a value if there is a 1. the value range goes from 128 and halving it each time.
what does it mean if the number at the end is a 1
its odd
what does it mean if the number at the end is a 0
its even
What are the two types of images?
Bitmap and vectors
Vectors?(3)
Used for line art and simple graphics. Each object is repersented by a formula. can be scaled up without loss of resolution.
Bitmap?(5)
used for photos and high quality graphics. repersented by a grid of pixals. each pixal a colour in binary. for 256 colours need 8 bits per pixal for two colours need 1 bit per pixal. become pixalated when scaled up.
What is a security breach?
incident where private data may have been stolen or veiwed
impact of a security breach? (4)
Reputaional damage, theft of personal info(idenity theft), moneyloss, damage
why somone would do a secruity brearch
for fun, challange, show how poor system is, steal credit card info to sell or use, steal personal info to use or sell
what makes a strong password
mix of upper and lower case letters, numbers, symbols
what is a diconary attack
computer tries password and then another until gets the right password
what is a brute force attack
changes parts of the password
malware?
programs that cause damage to the computer system
examples of malware
steals info, cause pop ups, slow down computer
what are the 5 types of malware
viruses, keyloggers, trogan horses, worms, spyware
viruses
causes damage or annoyance, need user interaction
worms
self replicating software that causes damage
trojan horses
appears harmless, used to install malware and create backdoors,
spyware
spy on users to get personal info and web browsing info
keyloggers
logs each keystroke made, used to steal password and sensitive info
what is antiviruses
program that is installed to block malware and suspisous programs. scans whole computer to check if anything matchs a virus, if find virus will quaritnine file soo can’t do anything.
