Changes

A '''computer''' is a machine that is designed to perform a wide variety of information-processing tasks, depending on the program it has stored in its memory.  It processes (computes) everything as mathematical problems, although many non-mathematical functions can be ultimately performed. Computers manipulate all data in the form of numbers, and encode all numbers in either [[binary|binary code]], which is base 2, or in the case of quantum computers, ternary code which is base 3. Binary means that there can only be a 1 or a 0 in any data.  This makes it possible to process data electronically, since one voltage can be used to represent a zero and another voltage for a one.  Ternary systems are far more complicated, and still in development.  The average personal or server computer uses binary.

A '''computer''' is a machine that is designed to perform a wide variety of information-processing tasks, depending on the program it has stored in its memory.  It processes (computes) everything as mathematical problems, although many non-mathematical functions can be ultimately performed. Computers manipulate all data in the form of numbers, and encode all numbers in either [[binary|binary code]], which is base 2, or in the case of quantum computers, ternary code which is base 3. Binary means that there can only be a 1 or a 0 in any data.  This makes it possible to process data electronically, since one voltage can be used to represent a zero and another voltage for a one.  Ternary systems are far more complicated, and still in development.  The average personal or server computer uses binary.

==History==

==History==

[[Image:Babbage.jpg|right|thumb|200px|Contemporary (1800's) illustration of what Charles Babbage's Difference Engine might have looked like.]]

[[Image:Babbage.jpg|right|thumb|200px|Contemporary (1800's) illustration of what Charles Babbage's Difference Engine might have looked like.]]

===Microcomputers===

===Microcomputers===

Microcomputers are computers that use microprocessors for the [[CPU]].  Some used the same instruction set as minicomputer CPUs, but implemented in one or two microprocessor chips, which allowed them to run the same software.  In some cases, these computers could timeshare several users just as minicomputers.  However, increasing CPU power and lower costs eventually led to the microcomputers being used by a single user at a time and being called "personal computers" (see below).

Microcomputers are computers that use microprocessors for the [[CPU]].  Some used the same instruction set as minicomputer CPUs, but implemented in one or two microprocessor chips, which allowed them to run the same software.  In some cases, these computers could timeshare several users just as minicomputers.  However, increasing CPU power and lower costs eventually led to the microcomputers being used by a single user at a time and being called "personal computers" (see below).

==Usage Classifications==

==Usage Classifications==

===Personal===

===Personal===

Personal computers are ones designed for use by a single user at any given time.   These are the common desktop and laptop computers most people use today.  Tablet computers could also be included in this general category.  Some businesses will include person computers in a client-server network.  In this system, the personal computers are used to connect with a main server computer (or in some cases, a server cluster).<ref name="WorldBook01">The World Book Encyclopedia. 2001 ed. Vol. 4. Chicago: World Book, 2001. Print. Pages 908-94</ref>

Personal computers are ones designed for use by a single user at any given time. These are the common desktop and laptop computers most people use today.  Tablet computers could also be included in this general category.  Some businesses will include person computers in a client-server network.  In this system, the personal computers are used to connect with a main server computer (or in some cases, a server cluster).<ref name="WorldBook01">The World Book Encyclopedia. 2001 ed. Vol. 4. Chicago: World Book, 2001. Print. Pages 908-94</ref>

===Client-server===

===Client-server===

*Optical disks have their foil melted by laser to show "zero" vs. "one"

*Optical disks have their foil melted by laser to show "zero" vs. "one"

*Flash memory has microscopic toggle switches which are set to "one" or "zero"

*Flash memory has microscopic toggle switches which are set to "one" or "zero"

Every part of a binary computer uses theses "ones" and "zeros" for everything.

Every part of a binary computer uses these "ones" and "zeros" for everything.

===Ternary (trinary)===

===Ternary (trinary)===

A new and evolving kind of computer breaks the "rules" of computer design entirely.  Using properties of [[quantum mechanics]], these computers make use of alternate states of matter which can only exist very near [[absolute zero]].  Using these, a [[quantum computer]] can not only use ones and zeros, but also a sort of "both one and zero."  Ternary processors must be kept incredibly cold, however.  Due to this requiement, as well as many other technical issues, ternary computers are not commercially available.  For now, these remain restricted to laboratories where space and liquid nitrogen are plentiful.  However, it is believed that they may  

A new and evolving kind of computer breaks the "rules" of computer design entirely.  Using properties of [[quantum mechanics]], these computers make use of alternate states of matter which can only exist very near [[absolute zero]].  Using these, a [[quantum computer]] can not only use ones and zeros, but also a sort of "both one and zero."  Ternary processors must be kept incredibly cold, however.  Due to this requirement, as well as many other technical issues, ternary computers are not commercially available.  For now, these remain restricted to laboratories where space and liquid nitrogen are plentiful.  However, it is believed that they may  

eventually replace binary computers.<ref>"quantum computer." Encyclopaedia Britannica. Britannica Academic. Encyclopædia Britannica Inc., 2016. Web. 31 May. 2016. <http://0-academic.eb.com.www.consuls.org/EBchecked/topic/746092/quantum-computer>.</ref>

eventually replace binary computers.<ref>"quantum computer." Encyclopaedia Britannica. Britannica Academic. Encyclopædia Britannica Inc., 2016. Web. 31 May. 2016. <http://0-academic.eb.com.www.consuls.org/EBchecked/topic/746092/quantum-computer>.</ref>