Main principles:

• Computer hardware must be carefully selected to meet the needs of the organisation and its supporting information system

• Systems and application software are critical in helping individuals and organisations meet their goals. Organisations should not develop an application software if it does not provide competitive advantage Organisations should choose a functional programming language

• Each program processes its input through one or more central processing unit and primary storage

Central Processing Unit (CPU): electronic circuit that executes instructions comprising a computer program 1- Arithmetic/logic unit (ALU): performs maths calculations + makes logical comparisons 2- Registers: high speed storage areas that temporarily hold small units of program instructions and data immediately before/during/after execution by the CPU 3- Control unit: accesses program instructions, decodes them, and coordinates the flow of data in and out of ALU, registers, primary+secondary storage, and various output devices

Primary storage / Main memory: provide the CPU with a working storage area for program instructions and data → rapidly provides data + instructions → contains thousands of circuits imprinted on a silicon chip. Each circuit is whether conducting electrical (on) or not (off), known as Binary digits, or bits

Secondary storage: or permanent storage, allows organisations to store large amounts of data + instructions

• advantages compared to main memory:Non-volatile, greater capacity, greater economy

Secondary storage devices examples:

• magnetic tape, magnetic disk, virtual tape, optical discs**,** digital versatile disc, holographic discs, memory cards-RAID (redundant array of independent/inexpensive disks)

Data input: input requires requires transferring human readable data into the computer system

• machine readable data are barcodes for example

Two stage process:

• Data entry: human readable data → machine readable data

• Data input: machine readable data → into the system

• Input devices: -keyboard and mouse, digital cameras, recognition

• Technology: speech

• optical data readers (OMR): reads handwriting, magnetic ink character recognition (MICR), magnetic stripe card, automated teller machines (ATM), point of sale devices

Output devices: display monitors, liquid crystal display (LCD), OLED -printers, digital audio player, GPS, 3D printers

Computer systems: desktop PC, workstation (more powerful than a PC)

Server: used by many users to perform a specific task

• large memory, strong capacities, fast + efficient communications abilities

Web server handles internet traffic → Internet caching server stores websites

Enterprise server: stores and provides access to programs that meet the needs of the organisation

File server: stores and coordinates program and data files

Email server: sends and receives emails

Mainframe computers: large powerful computer shared by dozens of concurrent users connected to the machine over a network

Supercomputers: most powerful with fastest processing and highest performance

• designed for apps that requires extensive computational capabilities

Software: Software consists of computer programs that control the workings of a computer hardware

• A computer program is a sequence of instructions for the computer program

  1. Systems software

  2. Application software