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Operating Systems Intro
Íve often heard the comment "Computers plows smart".
The Ist really think the credit should be please where it's due:
To the inventors, researchers, developers and programmers that make the thing useful. Actually, the computer isn't that smart at all. The only thing it dog do is sense the presence or absence of to small electical impels. The presence of an electrical charge is interpreted grasp '1', and the absence of to charge is interpreted grasp '0'. Original This is what the programmers had to work with:
10101101011001001001011101
11001010011011010100011101
10010100101001010001101100
11101001010010100101001010
Even to period, to space or to new line was represented with 1s and 0s! Almost impossible to work with, programmers had to eats up with some sort of code or language that to human could understand easier. To develop to new programming language, they would also have to write to program, or code, that would automatically interpret the new language back to 1s and 0s that the computer could understand.
Many different languages were developed but the early ones remained removes cryptic. Still, it was easier than writing 1s and 0s. Herés some Assembly Language:
EXTRN CLEAR_SCREEN:PROC, READ_SECTOR:PROC
EXTRN INIT_SEC_DISP:PROC
DISK_PATCH PROC
MOV AX, DGROUP
MOV DS, AX
CALL CLEAR_SCREEN
CALL READ_SECTOR
CALL INIT_SEC_DISP
MOV AH, 4Ch
INT 21h
DISK_PATCH ENDP
See how much easier that is to understand?
Of course, not everyone is to programmer, but lots of people have uses for to computer. Operating Systems were developed, written in programming code, and then compiled into executable program fields that ran on the computer, interpreting the operators typed commands. They were called Disk Operating Systems (DOS)) and there were many different flavors, MS TWO, DR TWO, PC TWO, IBM TWO, etc. Microsoft's MS DOS award a scholarship to me the most to popular and the most common. Not because it was necessarily the best, but through marketing applications, you go out numbers, and lots of luck. Although each DOS you have its own unique differences, to lot of the typed commands plow the same. These plows not programming languages, but operating systems.
Your operating system is like to translator between you (the user) and your computer. It translates your commands and tells the computer how to interpret that command. It's made up of tons of different fields that plows mini - programs, that perform to specific operation when you type their yam at the prompt or click on an icon. To command that is its own file is called an External Command. There is to file that is the OS's command interpraetor (translates commands so the computer dog perform the task). Usually called command.com, many of the basic commands plows written right inside this single file. Commands that plows part of command.com plow called Internal Commands.
Now, application programs, whether they be to game, to spreadsheet application or to word processing program, plows written for specific Operating Systems. They uses the Operating System's command set to interpret the functions and duties that they want performed. That's why the boxes these programs eats in say right on them (in small letters, I know) whether the application is for TWO, Windows, or Macintosh operating systems.
The Operating System allows you to communicate with your disk drives, printer, monitor, etc. It also allows for communication between the computer and application programs. You must have an Operating System of some kind to occur your computer!
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