1.2 Memory And Storage Flashcards
Bit
1 or 0
Nibble
4 bits
Byte
8bits
Kilobyte
1024 bytes (1000)
Megabyte
1024 kilobytes (1000 )
Gigabyte
1024 megabytes
Terabyte
1024 gigabytes
Petabyte
1024 terabytes
Why binary
Easier to represent only 2 states using electrical components
Overflow errors occur
When the number you are presenting is larger than 255 and you need an additional bit
Left shift is
Multiplication
Right shift is
Division
Hex
0123456789 ABCDEF
Character set
A set of characters each with a binary value assigned
ASCII is 7 bits how many characters?
127
Extended ASCII is 8 bits how many characters
255
Colour depth
Number of bits needed to store each pixel
Meta data
Extra info about an image
Greater the colour depth / resolution greater the…
File size
Sound file size calculation
Number of samples per second x number of bits per sample x length of sample
Sample rate
The number of samples taken per second (measured in Hertz)
Compression
Compression reduces the size of a file so it takes up less space
2 advantages of compression
Maximise amount you can store
Smaller files are quicker to transfer and download
Lossy
Loses data
Lossless
Doesn’t lose data
Order of byte
Byte kilobyte megabyte gigabyte terabyte petabyte
RAM
Random access memory
ROM
Read only memory
Primary storage
Storage needed for the computer to function
ROM RAM what and what
Registers and cache
RAM does what
Keep data currently in use so the CPU can access it quickly
ROM has what
Uneditable info that starts bootstrap (instructions needed to boot computer system)
Registers and cache are found
In the CPU
Registers do what
Have specific data and instructions
Cache do what
Store frequently used instructions
Which one isn’t volatile
ROM
What does volatile mean
Will disappear if power is lost
