CHAPTER 1 : INTRODUCTION TO COMPUTER

Introduction To Computer

Computer System Organization 

Hardware : 



CPU

 = Brain of the computer, most faster and expensive.To control unit, program counter, register introduction, arithmetic logic unit, accumulator.

MAIN MEMORY

= Temporary memory, volatile, directly connected to the CPU, using memory cells unit.

SECONDARY STORAGE(FLOPPY DISK)

= Provides permanent storage for information.Exp: Hard disks, floppy disks, Zip disks, CD-ROMS, Tapes.

INPUT DEVICES (WEBCAM)

 Such as webcam, pedal, joystick, wheel, microfon, scanner.

OUTPUT DEVICES (PRINTER)

Such as printer, monitor, projecter.

Software : 

 

Ø System software

- to control the computer

- handles a memory management, storage management,I/O activvities.

- Exp: Microsoft windows, MAS OS, Apple's(machintosh)

Ø Application software

- perform a specific task such as microsoft word, proccessors, games,photoshop.

- all application program written using computer programming language.

  

High Level Language - JAVA

•  JAVA called bytecode.
• Bytecode interpreted into particular machine language.
• Bytecode is different from other mesin language because it can read by Java Virtual Machine(JVM).
• Java bytecode runs on any computerthat has JVM.
• JVM is an interpreter that translates and executes bytecode.
• A compiler translates java code into bytecode.

    Processing a Java Program

Editor = write java code using java syntax(source code).

Compile = source code for correctness of syntax then translate into bytecode.

Linker = program in JDK library called LINKER link the bytecode with necessary code      residing in the library.

Loader = transfer the compiled code(bytecode) into main memory.

Interpreter = Read and translates each bytecode instruction into machine language then executes the statements in a program written in a high-level language. 

 Low Level Language

-Machine language is the language that can understand by computer.

-Assembly language is a symbolic form of machine language that easy for people read.

-Machine language same to assembly language but needs some minor additional translation to run the computer.