A computer is a general purpose device that can be programmed to carry out a set of arithmetic or logical operations
A computer consists of at least one processing element, typically a central processing unit (CPU) and some form of memory
Computer architecture defines basic attributes of hardware components and their interconnections to achieve specified goals in terms of functions and performance
Computer organization involves the design and physical arrangement of hardware units to work together in an orderly manner to achieve the goals specified in the architecture
Computer architecture comprises logical functions like instruction sets, registers, data types, and addressing modes
Computer organization consists of physical units like circuit design of peripherals and addresses
Examples of architecture attributes include the instruction set, number of bits to represent data types, I/O mechanisms, and memory addressing techniques
Organization attributes include hardware details transparent to the programmer, such as control signals, interfaces between the computer and peripherals, and memory technology used
Computer structure refers to the interrelation of components, while computer function refers to the operation of each individual component as part of the structure
Functions of a computer include input, storage, processing, output, and control
A computer consists of components like processor, memory, and I/O that communicate through a bus
Central processing unit (CPU) is responsible for executing instructions and performing calculations in a computer system
Main memory, or RAM, provides temporary storage for data and programs actively used by the CPU
I/O devices enable communication between the computer and the external world for input and output of data
System bus connects different components within a computer system to enable data, information, and control signal flow
Data bus transports data and instructions between components bidirectionally
Address bus sends address signals from the CPU to Main Memory in a single direction
Control bus sends control signals between components bidirectionally
The history of computing began with the abacus, followed by the development of programmable digital computers like Mark I
Computer generations evolved from vacuum tube-based first generation to integrated circuits in the third generation, and VLSI circuits in the fourth generation
Fifth generation computers use ULSI technology, parallel processing hardware, and AI software
Programming languages are designed to communicate instructions to a machine
Used to create programs that control the behavior of a machine
Types of programming languages:
High level
Low level
High level programming languages are more user-friendly and closer to human language
Low level programming languages are languages that the machine understands
Types of low level programming languages:
Assembly language:
Next lowest programming language to machine language
Specific to particular computer architecture
Source code is converted into executable machine code by an assembler
Machine language:
Lowest level of computer language consisting of binary codes
Produced by compiling high-level source code for a specific processor
Software developers do not need to manipulate the machine code except for systems' programmers
Writing an assembly language program requires knowledge of PC hardware and details of various instruction sets
PC hardware components:
Processor
Memory
I/O
Connected through a bus, a communication pathway transferring data between the processor, memory, and external devices
The processor:
Responsible for executing instructions and processing data
Different processors vary in speed and capacity of memory, registers, and data bus
System bus:
Wires on the motherboard connecting the CPU to other components
Data bus:
Transports data and instructions between components