Glossary - Revision history

Clemtre: unnecessary sanism + US centered

2024-01-07T14:41:41Z

unnecessary sanism + US centered

Zzo38: The decimal use of SI prefixes for bytes is more common for measurement of the capacity of hard drives.

2021-11-14T10:40:36Z

The decimal use of SI prefixes for bytes is more common for measurement of the capacity of hard drives.

Kayvon2008 at 07:51, 14 November 2021

2021-11-14T07:51:01Z

Kayvon2008 at 07:49, 14 November 2021

2021-11-14T07:49:27Z

Jsummers: Category:Information

2017-06-10T16:24:40Z

Category:Information

Dan Tobias at 03:21, 24 March 2016

2016-03-24T03:21:11Z

Dan Tobias at 03:20, 24 March 2016

2016-03-24T03:20:57Z

Dan Tobias at 03:20, 24 March 2016

2016-03-24T03:20:28Z

Sam888 at 23:17, 23 March 2016

2016-03-23T23:17:38Z

Sam888: formatting for easier reading

2016-03-23T23:17:04Z

formatting for easier reading

Show changes

@@ Line 27: / Line 27: @@
 ;'''Floating point''': A type of numeric storage that allows fractional parts expressed as decimal places, and an exponent indicating where the decimal point is placed.
-;'''Forensics''': The study of finding information for a case. This includes extracting and using iPhone photos because a psychopath killed a random poor guy, and grabbing a suspected terrorist's laptop hard disc and using browsing history to see if the guy can go to the US or not. Information and experience used in this field has the same goal as us. To decode data.
+;'''Forensics''': The study of finding information for a case. This includes extracting and using iPhone photos for a murder case, and grabbing a suspected terrorist's laptop hard disc and using browsing history to ensure state security. Information and experience used in this field has the same goal as us. To decode data.
 ;'''Gigabyte''': 1024 (or 1000) megabytes. Once an exotic term in the days when computer memory and disk space was typically measured in kilobytes, it is now commonplace even in measuring the size of small and cheap [[thumb drive]]s.

@@ Line 19: / Line 19: @@
 ;'''Bitmap''': An image stored as a set of groups of bits representing the color value of each pixel of the image, which can be mapped onto a display medium (screen or printer) for output. A black-and-white bitmap needs only one bit per pixel, while color images need more bits depending on the number of different colors supported. The values used for each pixel might be numeric indices within some enumerated palette of colors, or direct renditions of the color (e.g., by "RGB" values specifying the amount of red, green, and blue making up the color).
-;'''Byte''': A group of eight bits, sometimes also referred to as an "octet". This is how computer memory is traditionally organized. Usually a byte is treated as a unit, representing a number from 0 to 255 or else a text character in an encoding such as [[ASCII]], but some file formats delve into the individual bits; the 8 bits which make up a byte are arranged from the "high-order bit" to the "low-order bit" (or vice versa; see [[Bit order]]) based on where they fall in the binary number represented by them; as with conventional decimal numbers, the leftmost one has the highest value and is the "high-order bit". (How they're physically arranged on the storage medium depends on the characteristics of the specific device. This is usually not of concern to programmers of anything above low-level device drivers and processor microcode; normal developers see only the abstract logical structure of the bits and bytes.) In raw memory dumps, a byte will often be displayed as two hexadecimal digits.  (''Byte'' is also a computer magazine published since the 1970s.)
+;'''Byte''': A group of eight bits, sometimes also referred to as an "octet". This is how computer memory is traditionally organized. Usually a byte is treated as a unit, representing a number from 0 to 255 or else a text character in an encoding such as [[ASCII]], but some file formats delve into the individual bits; the 8 bits which make up a byte are arranged from the "high-order bit" to the "low-order bit" (or vice versa; see [[Bit order]]) based on where they fall in the binary number represented by them; as with conventional decimal numbers, the leftmost one has the highest value and is the "high-order bit". (How they're physically arranged on the storage medium depends on the characteristics of the specific device. This is usually not of concern to programmers of anything above low-level device drivers and processor microcode; normal developers see only the abstract logical structure of the bits and bytes.) In raw memory dumps, a byte will often be displayed as two hexadecimal digits. (''Byte'' is also a computer magazine published since the 1970s.)
 ;'''Digital''': The inverse of "analog", meaning a set of data which has been digitized (if it originated in an analog medium), or else created natively on a digital device such as a computer. There are no continuously-variable quantities in a digital data set, only a set of discrete elements which can be converted into a series of bits for storage. Images, for instance, are broken up into pixels at some stated resolution, each of which can have one of a finite set of color values.  Sounds are sampled at some sampling rate to capture the state of the sound wave at that point.
@@ Line 41: / Line 41: @@
 ;'''Kilobit''': 1000 (or 1024) bits, or 1/8 of a kilobyte. Transfer protocols usually measure their speed in bits per second (or multiples thereof) rather than bytes, so you have to divide by 8 to get the number of bytes (or kilobytes, etc.) transferred in a second.
-;'''Kilobyte''': Either 1000 bytes (the literal meaning of the metric prefix "kilo") or, more often, 1024 bytes (a power of two, which makes it a "round number" to a computer). Attempts to resolve the ambiguity by introducing a new term "kibibyte" for 1024 bytes to leave "kilobyte" meaning 1000 haven't gone anywhere.
+;'''Kilobyte''': Either 1000 bytes (the literal meaning of the metric prefix "kilo") or, more often, 1024 bytes (a power of two, which makes it a "round number" to a computer). Attempts to resolve the ambiguity by introducing a new term "kibibyte" for 1024 bytes to leave "kilobyte" meaning 1000 haven't gone anywhere. The decimal use of SI prefixes for bytes is more common for measurement of the capacity of hard drives.
 ;'''Little-Endian''': The system of storing numeric values which take up more than one byte in a manner in which the low-order byte comes first. If a number takes up more than 8 bits to store (e.g., an integer larger than 255), it must be divided between bytes, and it becomes an issue in file format definitions whether the "smaller-valued" parts of the number come in the first byte or the last one. See [[Endianness]].

@@ Line 72: / Line 72: @@
 ;'''Vector graphics''': Graphics expressed as a group of vectors specifying coordinates of a starting point (or specifying that the vector starts at the point the previous vector ended), the vector direction and length (by an angle and length, or by specifying an endpoint), and the drawing status for the vector (e.g., move without drawing, draw a line of specified color, draw a stored shape, etc.). This is as opposed to raster graphics which specify each pixel's content. Vector graphics are rendered by following the instructions in the file as to what lines and shapes to draw.
-;'''Yottabyte''': 1024 (or 1000) zettabytes. No system has come near containing this much information yet, but supposedly the US government data snoops at the NSA are gearing up to store data on that scale.
+;'''Yottabyte''': 1024 (or 1000) zettabytes. No system has come near containing this much information yet, but supposedly the US government data snoops at the NSA are gearing up to store data on that scale, but this might be the average cellphone storage in 50 years.
 ;'''Zettabyte''': 1024 (or 1000) exabytes. The entire amount of information on the World Wide Web has been estimated at half a zettabyte.

← Older revision		Revision as of 07:49, 14 November 2021
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	;'''Floating point''': A type of numeric storage that allows fractional parts expressed as decimal places, and an exponent indicating where the decimal point is placed.		;'''Floating point''': A type of numeric storage that allows fractional parts expressed as decimal places, and an exponent indicating where the decimal point is placed.
		+
		+	;'''Forensics''': The study of finding information for a case. This includes extracting and using iPhone photos because a psychopath killed a random poor guy, and grabbing a suspected terrorist's laptop hard disc and using browsing history to see if the guy can go to the US or not. Information and experience used in this field has the same goal as us. To decode data.

	;'''Gigabyte''': 1024 (or 1000) megabytes. Once an exotic term in the days when computer memory and disk space was typically measured in kilobytes, it is now commonplace even in measuring the size of small and cheap [[thumb drive]]s.		;'''Gigabyte''': 1024 (or 1000) megabytes. Once an exotic term in the days when computer memory and disk space was typically measured in kilobytes, it is now commonplace even in measuring the size of small and cheap [[thumb drive]]s.

← Older revision		Revision as of 16:24, 10 June 2017
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	== Links ==		== Links ==
	* [http://www.ribbonfarm.com/2014/02/07/an-information-age-glossary/ An Information Age Glossary] (more philosophical than practical)		* [http://www.ribbonfarm.com/2014/02/07/an-information-age-glossary/ An Information Age Glossary] (more philosophical than practical)
		+
		+	[[Category:Information]]

@@ Line 7: / Line 7: @@
 :The commands and arguments in a batch file are executed in sequence.
 :'''Batch files''' [http://technet.microsoft.com/en-us/library/bb490869.aspx] are run by the '''command.com''' [http://www.microsoft.com/resources/documentation/windows/xp/all/proddocs/en-us/ntcmds_shelloverview.mspx?mfr=true] program, and use the file extension '''.bat''' and can only be run on Windows or PC/MS-DOS machines. ([[Batch file|Full article]])
-(''see '''Shell Scripts''' for similar files for Unix, Linux and Apple computers'')
+:(''see '''Shell Scripts''' for similar files for Unix, Linux and Apple computers'')
 ;'''Baud''': Sometimes treated as a synonym for "bits per second" in transfer protocols, but not actually synonymous; it refers to the number of signal changes per second, e.g., in a modem. Early modems transferred one bit per signal change, so a 300-baud modem got 300 bits per second, but later modems used more sophisticated protocols that transferred multiple bytes per signal change by using more distinct types of signals, so "bps" (or "kbps", "mbps", etc.) is the more appropriate term to use when discussing the amount of data a device, network, or protocol can transfer.

@@ Line 4: / Line 4: @@
 ;'''Batch File''': A script (on PC/MS-DOS or Windows systems) that contains commands and arguments to automate routine tasks. These commands and arguments can be run by typing them into the terminal or saved and run whenever needed saving time and effort.  They can be edited if necessary to accomodate changes in the work environment they are used in.
-These scripts are mini programs that do narrowly defined tasks and are written in a text editor. Generally having to do with file and disk management, they can do many other things as well. They can written to ask for user input and respond accordingly.  Many network administration tasks can be automated with batch files.  They can also be used to control the behaviour of other programs.
+:These scripts are mini programs that do narrowly defined tasks and are written in a text editor. Generally having to do with file and disk management, they can do many other things as well. They can written to ask for user input and respond accordingly.  Many network administration tasks can be automated with batch files.  They can also be used to control the behaviour of other programs.
-The commands and arguments in a batch file are executed in sequence.
+:The commands and arguments in a batch file are executed in sequence.
 '''Batch files''' [http://technet.microsoft.com/en-us/library/bb490869.aspx] are run by the '''command.com''' [http://www.microsoft.com/resources/documentation/windows/xp/all/proddocs/en-us/ntcmds_shelloverview.mspx?mfr=true] program, and use the file extension '''.bat''' and can only be run on Windows or PC/MS-DOS machines. ([[Batch file|Full article]])
 (''see '''Shell Scripts''' for similar files for Unix, Linux and Apple computers'')
@@ Line 58: / Line 58: @@
 ;'''Shell Scripts''': Linux, Unix and Apple systems have scripting schemes that do the same jobs that batch files ('''.bat''') do in Windows machines, and run are run from their terminals.  They are called '''Shell Scripts''' [http://www.arachnoid.com/linux/shell_programming.html] and in Linux and Unix typically use the file extension '''.sh''' although there are others sometimes used.  For Apple computers the scripts are written in '''Applescript''' [https://developer.apple.com/library/mac/#documentation/AppleScript/Conceptual/AppleScriptX/AppleScriptX.html] and the file extension is '''.scpt'''.  These scripts can have variables and flow control statements (e.g. goto, if-then-else, while, for,)
-Like their counterparts in Windows, these scripts are executable, and can be saved to automate tasks and be edited as needed.  The file extension in Linux and Unix is not really required, what makes them what they are is controlled by the first line of the script itself and it needs to be made executable by the owner of the file. (''see '''Batch Files''' for Windows equivalent'')
+:Like their counterparts in Windows, these scripts are executable, and can be saved to automate tasks and be edited as needed.  The file extension in Linux and Unix is not really required, what makes them what they are is controlled by the first line of the script itself and it needs to be made executable by the owner of the file. (''see '''Batch Files''' for Windows equivalent'')
 ;'''Soft sector''': A disk or other storage medium that does not have hard sectors (marked physically such as with punched holes), so the sector positions need to be established by the software when a disk is formatted.