Hardware & Software

Hardware

physical equipment used for the input, processing, output, and storage activities of a computer system

Servers

• In the client/server computing model, the server awaits & fulfills a request from a client

• Similar to desktop computers, but are:

  • configured with greater quantities of computing
    resources

  • Designed to support redundancy for continuous
    function even if a key component fails

Central Processing Unit (CPU)

• Silicon chip performing the computation in any computer

• millions of microscopic transistors embedded in a circuit

•CPU Characteristics:

Bandwidth:

• the Number of Cores -  total number of threads that a processor package is capable of executing simultaneously

•bits processed by a single instruction (32-bit; 64-bit)

Clock Speed:

•determines how many clock ticks per second can be executed.

•Measured in hertz (Hz); Mega or Giga (GHz)

–Ex: 4GHz… 4 billion ticks a second

Memory Capacity Hierarchy

• Bit =  0s & 1s

• Byte = 8 bits = needed to represent just one character

• Kilobyte (KB) = 1024 bytes.

  • Megabit (Mb) = 128 KB : (Internet Speed Measurement)

• Megabyte (MB) = 1024KB = 8 Megabits (Mb)

• Gigabyte (GB) = 1024MB

• Terabyte: One trillion bytes.

• Petabyte: One thousand terabytes.

• Exabyte: One thousand petabytes.

• Zettabyte: one thousand exabytes.

Primary Storage

• Volatile storage the CPU directly accesses

• Meaning it will lose its contents when the power is turned off

• Ex: Random Access Memory(RAM), Cache Memory, Registers

Secondary Storage

• Non-volatile storing large amounts of data for a long time

• Cheaper than Primary Storage

• Types:

  • Storage/Hard drives, Memory Cards, Thumb/USB Drives

Input Devices

• Human based entry: e.x. keyboards, web cam, microphones, stylus

• Gesture Based Data Entry: e.x. technologies interpreting human gestures/body language

• Source Data Automation: e.x. magnetic chip reader, barcode scanner

Output Devices

• generated by a computer can be transmitted to the user over several output devices and media, which include:

• e.x. Monitors, Printers, Speakers

Software

• set of computer programs that enable the hardware to process data.

• Largest percentage of the cost for modern computer information systems

Programming

• Process of writing or coding programs

• Many programming languages can be used

• Code written is known as source code

System Software

Set of instructions that serve primarily as an intermediary between computer hardware & application programs

Application Software

• Set of instructions that direct a computer system to perform specific processing activities & provide functionality for users.

  • Word Processors, Personal Finance, Presentation

• •Installed on top of the operating system offering a specific functionality to the user

• Package or Suite

  • Groups of software programs with integrated functions that is available for purchase

  –Examples:

  •Microsoft Office Suite, Adobe Creative Suite

Operating System

• Controls the operations of the computer

• Allocates CPU time & memory to programs

• Provides an interface between the user & the hardware

• e.x. Windows, Mac OS, Linux, Chrome OS

Interfaces

• Graphical User Interface (GUI)

  • allows users to have direct control of visible objects (such as icons) and actions, which replace command syntax

• Social Interface

  • Software agent guiding users through computer applications mainly through voice commands

  • e.x. Mobile Personal Assistants, Siri, Google Assistant, Virtual Assistants

Acquiring Software

• Can be developed in house by personnel & contracted to a software company

• Can be purchased, leased or rented from a software vendor…

  • known as Commercial Off The Shelf (COTS)

• Freely available software from the web, but could have restrictions on distributing it

Software Issues

• Software Defects

  • Program code that is inefficient, poorly designed & causes errors

  • Programmers made between 100-150 errors for every 1,000 lines of code written

• Software Licensing

  • Use of proprietary software or duplication of it without purchasing a license or getting manufacturer’s consent.

  • Doing without manufacturer’s permissions is known as piracy