fixed merge Lesson2

Lesson2.md

@@ -11,7 +11,6 @@ The Command Line Interface is the most common and pervasive interface directly l
 
 The aim of this lesson is for readers to develop an appreciation of the advantages of using the CLI for certain types of work involving text editing on a computer. As the CLI itself is text based, our goal is to present the history of the CLI and discuss how text-based computer interfaces are still up to this day on of the most important ways to communicate with the computer systems.
 
-<<<<<<< HEAD
 The goals of the lesson are:
 
 1. Understand the historical precedents leading to the development of modern CLI.
@@ -23,9 +22,9 @@ The goals of the lesson are:
 
 ### History
 
-We can trace back the history of the text-based interface as mode operating computers to the telegraph and of course the typewriter. Years before computing (as we know it) was invented[REF: Turing], the telegraph was already a ubiquitous telecommunication system. Early operators of the telegraph used hand-operated devices, the Morse key, to send Morse codes down the communication cable, an interface that had many limitations due to it's rather crude operation mode. From the mid 19th century on, a few devices were invented that featured a multiple keys keyboard interface and related receiver apparatus that would print messages sent using the keyboard input device. These greatly improved the speed in which messages could be sent and received. However, messages printed using these devices were still encoded raw; a received message would usually be in punched holes format on a piece of paper tape. For this reason, trained operators capable of deciphering such codes were still key interpreters of the wired cables.
+We can trace back the history of the text-based interface as mode operating computers to the telegraph and of course the typewriter. Years before computing (as we know it) was invented, the telegraph was already a ubiquitous telecommunication system. Early operators of the telegraph used hand-operated devices, the Morse key, to send Morse codes down the communication cable, an interface that had many limitations due to it's rather crude operation mode. From the mid 19th century on, a few devices were invented that featured a multiple keys keyboard interface and related receiver apparatus that would print messages sent using the keyboard input device. These greatly improved the speed in which messages could be sent and received. However, messages printed using these devices were still encoded raw; a received message would usually be in punched holes format on a piece of paper tape. For this reason, trained operators capable of deciphering such codes were still key interpreters of the wired cables.
 
-It is not until the beginning of the 20th century, with the advent of the Teletype (TTY) [REF: Crumb], that sending and receiving tele-typed text over telegraph lines was fully automated. Quite similar to the typewriter, a TTY made reading and writing encoded text seamless: the teletypewriter would encode typed alphabetic characters and the teletypeprinter would decode received encoded characters in an alphabetic format. Hence sending a message to an endpoint would be as easy as typing on a normal typewriter. This new type of telecommunication interface greatly changed the face of news and print media[REF] as it enable reporters and writers to send and receive "cables" on their own (without the need to be trained operators themselves). 
+It is not until the beginning of the 20th century, with the advent of the Teletype (TTY), that sending and receiving tele-typed text over telegraph lines was fully automated. Quite similar to the typewriter, a TTY made reading and writing encoded text seamless: the teletypewriter would encode typed alphabetic characters and the teletypeprinter would decode received encoded characters in an alphabetic format. Hence sending a message to an endpoint would be as easy as typing on a normal typewriter. This new type of telecommunication interface greatly changed the face of news and print media as it enable reporters and writers to send and receive "cables" on their own (without the need to be trained operators themselves). 
 
 But why is the history of the TTY important for our concern here? Well there's two major reasons. First, the Teletype was historically important for the development of text encoding ([Lesson1](Lesson1.html)). Early Teletype machines used the Baudot code encoding scheme but Teletype Model 33 (a standard TTY device in the 1960's and 1970's) used the ASCII encoding scheme. For this reason, ASCII (and modern UTF-8) has, still to this days, control codes that refer to networking operational commands. These characters attest the legacy of TTY devices. Second, as a result of ASCII integration in Model 33, the TTY became an central interface to mainframe computing machinery in the 1960's and 1970's. Before the advent of the TTY, the standard computing interface was the punch card format. TTY introduced direct input of computing commands from the teletypewriter and formalised the output as teleprinted on paper (ASCII also have printing control codes). For a long period of time, the main medium of computing was printed paper.[^1]
 
@@ -38,75 +37,11 @@ The first terminal to showcase a screen as output device (rather than paper) was
 
 The direct descendant of the Datapoint 3300, the Datapoint 2200 was the first programmable terminal, viewed by many as the first personal computer. The fact that the Datapoint 2200 was programmable, meaning that code could be written for and ran on the terminal's circuit itself and not on a mainframe made it very attractive to computer programmers. Commands could be issued on the Command Line Interface and directly resolved locally without the need of an (expensive) mainframe. 
 
-This is were the story of terminals ends. If code is executed locally and not remotely, it is erroneous to talk about a terminal but instead must 
+This is were the story of terminals ends. If code is executed locally and not remotely, it is erroneous to talk about a terminal porperly saying but instead once must talk about the CLI (i.e., no more remote terminal but he emulation of the mainframe, as for the Datapoint 2200).
-
-No more terminal but he emulation of the mainframe -- same look and feel 
-
-
-Computer Terminal Corporation -- 
-Datapoint3300 --- first video / visual terminal
-Datapoint2200 --- emulation of the terminal = PC
-
-Intel 8008 - Intel 8080
-
-1972 UNIX
-
-Microcomputers
-1974 CP/M 86 --- IBM PC -- INtel 8086( "Control Program/Monitor")
-DOS
-1978 Apple-DOS
-1979 Atari-DOS
-1981 PC-DOS
-
 
 ### How
 
-Command Line Interface ---> Command Line Interpreter (shell)
+To access to the Command Line Interface of your computer you need a Command Line Interpreter. Every mdoern Operating System (OS) have such interpreter built-in. In fact, the Command Line Interpreter are legacy systems on most OS (OSX, Windows, Linux, Unix, etc.) because there was a time when interfacing with a computer was solely done typing commands on a terminal.[^5] Most computer programmers, even nowadays, use the computer CLI on a daily basis to write and run software and even to debug hardware.  
-
-Prompt
-
-Commands
-
-<!--
-<ls>
-
-<mv>
-
-<cp>
-
-<file>
-
-<fmt> <fold>
-
-<iconv>
-
-<wc> + <nl>
-
-<grep>
-
-Results
-
-### Extra
-
-<banner>
--->
-
-[^1]: Something that is easily forgotten in the era of ubiquitous computer screens. For a discussion on the topic see Nick Montfort's essay [Continuous Paper: The Early Materiality and Workings of Electronic Literature](http://nickm.com/writing/essays/continuous_paper_mla.html).
-
-[^2]: [Datapoint 3300 brochure](http://archive.computerhistory.org/resources/text/Computer_Terminal_Corporation/ComputerTerminalCorporation.Datapoint3300.1969.102646159.pdf).
-
-[^3]: In fact Victor Poor from CTC devised the architecture and instruction set. The instruction set is, to this day, found (a revised version of course) on Intel's flagship x86 architecture, the most pervasive microprocessor architecture of all time (typing this text was processed by a x86 microprocessor).
-
-[^4]: And subsequently the legacy 8-bit Intel 8080, 16-bit Intel 8086 and the whole x86 family of microprocessors. For all the details of the development of the Intel 8008, please refer to [this document](http://archive.computerhistory.org/resources/access/text/2012/07/102657982-05-01-acc.pdf).
-=======
-The goals of this lesson are:
-
-1. Acquire basic knowledge on how to operate the CLI of your own computer. 
-2. Acquire just-enough CLI vocabulary to be used in future work.
-
-### How
-
-To access to the Command Line Interface of your computer you need a Command Line Interpreter. Every mdoern Operating System (OS) have such interpreter built-in. In fact, the Command Line Interpreter are legacy systems on most OS (OSX, Windows, Linux, Unix, etc.) because there was a time when interfacing with a computer was solely done typing commands on a terminal.[^1] Most computer programmers, even nowadays, use the computer CLI on a daily basis to write and run software and even to debug hardware.  
 
 Depending on which OS you are using, accessing its CLI is quite simple:
 
@@ -188,18 +123,44 @@ It is, of course, out of the scope of this lesson to present all possible comman
 
 ### Extra
 
-[OSX Unix Tutorial for Beginners](http://acad.coloradocollege.edu/dept/PC/sciCompLab/UnixTutorial/)
+[Unix Tutorial for Beginners](http://acad.coloradocollege.edu/dept/PC/sciCompLab/UnixTutorial/)
 
 [A beginners guide to the Command Prompt (Windows)](http://www.codejacked.com/a-beginners-guide-to-the-command-prompt)
 
 
 A list of all commands: [OSX](http://ss64.com/osx/) - [Windows](http://ss64.com/nt/)
 
+### References
 
+[^1]: Something that is easily forgotten in the era of ubiquitous computer screens. For a discussion on the topic see Nick Montfort's essay [Continuous Paper: The Early Materiality and Workings of Electronic Literature](http://nickm.com/writing/essays/continuous_paper_mla.html).
 
+[^2]: [Datapoint 3300 brochure](http://archive.computerhistory.org/resources/text/Computer_Terminal_Corporation/ComputerTerminalCorporation.Datapoint3300.1969.102646159.pdf).
 
-[^1]: Something that is easily forgotten in the era of ubiquitous computer Graphical User Interface (GUI). The CLI is to some degree reminescent of the Teletype (TTY).
+[^3]: In fact Victor Poor from CTC devised the architecture and instruction set. The instruction set is, to this day, found (a revised version of course) on Intel's flagship x86 architecture, the most pervasive microprocessor architecture of all time (typing this text was processed by a x86 microprocessor).
+
+[^4]: And subsequently the legacy 8-bit Intel 8080, 16-bit Intel 8086 and the whole x86 family of microprocessors. For all the details of the development of the Intel 8008, please refer to [this document](http://archive.computerhistory.org/resources/access/text/2012/07/102657982-05-01-acc.pdf).
+
+[^5]: Something that is easily forgotten in the era of ubiquitous computer Graphical User Interface (GUI). The CLI is to some degree reminescent of the Teletype (TTY).
 
 <!-- Notes -->
 
 <!-- GUI / Xerox Star - http://members.dcn.org/dwnelson/XeroxStarRetrospective.html -->
+
+<!-- 
+
+Computer Terminal Corporation -- 
+Datapoint3300 --- first video / visual terminal
+Datapoint2200 --- emulation of the terminal = PC
+
+Intel 8008 - Intel 8080
+
+1972 UNIX <----------------------------- commands... this is very much missing here.... 
+
+Microcomputers
+1974 CP/M 86 --- IBM PC -- INtel 8086( "Control Program/Monitor")
+DOS
+1978 Apple-DOS
+1979 Atari-DOS
+1981 PC-DOS
+
+-->