Difference between revisions of "CS Terms - Getting Started"

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(Storage)
(Binary/Hex/integer limits)
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* TB - terabyte, 1 trillion bytes
 
* TB - terabyte, 1 trillion bytes
  
=Binary/Hex/integer limits=
+
=Base systems=
 +
* Able to convert between decimal, binary, hexadecimal, octal
 
* 15 = 1111 binary = F hex
 
* 15 = 1111 binary = F hex
 
* 255 = 1111 1111 binary = FF hex
 
* 255 = 1111 1111 binary = FF hex
* unsigned 8 bit integer is at most 255
+
* unsigned 8 bit integer ranges from 0 to 255
 
* signed 8 bit integer is between -128 and 127
 
* signed 8 bit integer is between -128 and 127
 
* unsigned 32 bit integer ranges from 0 to  2<sup>32</sup>-1, about 4 billion
 
* unsigned 32 bit integer ranges from 0 to  2<sup>32</sup>-1, about 4 billion
 
* signed 32 bit integer ranges from -2<sup>31</sup> to 2<sup>31</sup>-1, about +/-2 billion
 
* signed 32 bit integer ranges from -2<sup>31</sup> to 2<sup>31</sup>-1, about +/-2 billion
 
* unsigned k bit integer at most 2<sup>k</sup>-1
 
* unsigned k bit integer at most 2<sup>k</sup>-1

Revision as of 20:20, 6 January 2020

Storage

  • bit is 0 or 1, stands for “binary digit”
  • byte is 8 bits, written for example like 1001 0101
  • B - abbreviation for byte
  • b - abbreviation for bit
  • KB - kilobyte, 1000 bytes
  • MB - megabyte, 1 million bytes
  • GB - gigabyte, 1 billion bytes
  • TB - terabyte, 1 trillion bytes

Base systems

  • Able to convert between decimal, binary, hexadecimal, octal
  • 15 = 1111 binary = F hex
  • 255 = 1111 1111 binary = FF hex
  • unsigned 8 bit integer ranges from 0 to 255
  • signed 8 bit integer is between -128 and 127
  • unsigned 32 bit integer ranges from 0 to 232-1, about 4 billion
  • signed 32 bit integer ranges from -231 to 231-1, about +/-2 billion
  • unsigned k bit integer at most 2k-1