MIS 315-05

1

TG 1 Review

• Central processing unit (CPU) performs the actual computation or “number crunching” inside any computer.– A microprocessor incorporates most or all of the functions of a CPU on a single

integrated circuit (IC). A Microprocessor is made up of millions of microscopic transistors embedded in a circuit on a silicon chip.

– The clock rate of a CPU is only useful for providing comparisons between chips in the same processor family.

• ROM stands for read-only memory. A ROM chip is programmed with a permanent collection of pre-set bytes. – The BIOS (Basic Input/Output System) is stored in ROM. When a

microprocessor starts, it begins executing instructions it finds in the BIOS. The BIOS instructions do things like test the hardware in the machine.

• RAM stands for random-access memory. RAM contains bytes of information, and the microprocessor can read or write to those bytes. One problem with today's RAM chips is that they forget everything once the power goes off (volatile memory). That is why the computer needs ROM.

• Moore’s Law=microprocessor complexity would double every two years.

MIS 315-05

2

TG 1 Review

Is cache memory RAM or ROM?

MIS 315-05

3

TG 1 Review

MIS 315-05

4

TG 1 Review

MIS 315-05

5

TG 1 Review

MIS 315-05

6

Representing Numbers, Characters (Text), Pictures, and Sound

• Numeric data– Composed of numbers that might be used in

arithmetic operations. – Decimal number system has 10 symbols. – Binary number system has only two

symbols (0, 1).

• Character data– Composed of letters, symbols, and numerals

that are not used in arithmetic operations.– ASCII, Extended ASCII, EBCDIC, and

Unicode.

• Picture Data– Composed of a series of dots.– Each dot is assigned a binary number for

color.

• Sound Data– Is characterized by the properties of a sound

wave. – The wave can be represented digitally by

sampling it a various points and converting those points into digital numbers.

MIS 315-05

7

TG 1 ReviewNumeric & Character Data Representation

MIS 315-05

8

TG 1 ReviewHierarchy of Memory Capacity

• Bit – One binary digit

• Byte– 8 bits

• Kilobyte (KB)– Approximately one thousand

bytes, (1024 or 210 bytes)

• Megabyte (MB) – Approximately one million

bytes (1,048,576 bytes, or 1,024 x 1,024 or 220 bytes).

• Gigabyte (GB) – Actually 1,073,741,824 bytes

(1,024 x 1,024 x 1,024 or 230 bytes).

• Terabyte – One trillion bytes, or 240

bytes.

• Petabyte – One thousand terabytes,

or 250 bytes.

• Exabyte– One thousand petabytes,

or 260 bytes.

• Zettabyte– One thousand exabytes.

8

MIS315 - 05

TECHNOLOGY GUIDE TWO

Computer Software

MIS 315-05

10

Technology Guide Outline

• TG2.1 Significance of Software

• TG2.2 Systems Software

• TG2.3 Application Software

• TG2.4 Software Issues

• TG2.5 Programming Languages

MIS 315-05

11

Learning Objectives

• Differentiate between the two major types of software.

• Describe the general functions of the operating system.

• Describe the major types of application software.

• Describe the major software issues that organizations face today.

• Discuss the advantages and disadvantages of open-source software.

• Explain how software has evolved and consider trends for the future.

MIS 315-05

12

TG2.1 Significance of Software

• Computer program – The sequences of instructions for the computer, which

comprise software.– Stored program concept

• Modern hardware architecture in which stored software programs are accessed and their instructions are executed (followed) in the computer’s CPU, one after another.

• Documentation– Written description of the functions of a software program.

MIS 315-05

13

Hardware is useless without software

• By itself, hardware has no inherent capabilities.

• Hardware can only be made useful through the instructions that are executed on it.

• Those instructions are contained in software.

• Therefore, hardware is ‘nothing’ without software.

MIS 315-05

14

Types of Software

• Application software– The class of computer instructions that directs a computer

system to perform specific processing activities and provide functionality for users.

• System software– Class of computer instruction that servers primarily as an

intermediary between computer hardware and application programs.

– Provides important self-regulatory functions for computer systems, such as loading itself when the computer is first turned on, managing hardware resources such as secondary storage for all applications, and providing commonly used sets of instructions for all applications to use.

MIS 315-05

15

Significance of Software

MIS 315-05

16

TG2.2 Systems Software

• System Control Programs– Software programs that control the use of the hardware,

software, and data resources of a computer system.– Operating system

• The main system control program, which supervises the overall operations of the computer, allocates CPU time and main memory to programs, and provides an interface between the user and the hardware.

• Systems Support Software– Supports the operations, management, and users of a computer

system by providing a variety of support services. – System utility programs, performance monitors, and security

monitors are examples of system support programs.

MIS 315-05

17

Functions of the Operating System

• Multitasking/ multiprogramming– The management of two or more tasks, or programs, running concurrently on the

computer system (one CPU).

• Multithreading– A form of multitasking that runs multiple tasks within a single application

simultaneously.

• Multiprocessing– Simultaneous processing of more than one program by assigning them to different

processors (multiple CPUs).

• Virtual Memory– A feature that simulates more main memory than actually exists in the computer

system by extending primary storage into secondary storage.

• Graphical user interface (GUI)– System software that allows users to have direct control of visible objects (such as

icons) and actions. Used to replace command syntax.

• Social interface– A user interface that guides the user through computer applications by using

cartoonlike characters, graphics, animation, and voice commands.

MIS 315-05

18

Example of Social Interface Using an Avatar

Avatar

www.kurzweilai.net

MIS 315-05

19

System Support Programs

• System support programs– Software that supports the operations management and users of a

computer system by providing a variety of support services (e.g. system utility programs, performance monitors, and security monitors).• System utilities

– Programs that accomplish common tasks such as sorting records, locating files, and managing memory usage.

• System performance monitors– Programs that monitor the processing of jobs on a

computer system and monitor system performance in areas such as processor time, memory space and application programs.

• System security monitors– Programs that monitor a computer system to protect it and

its resources form unauthorized use, fraud, or destruction.

MIS 315-05

20

TG2.3 Application Software

• Off-the-shelf application software– Software purchased, leased, or rented from a vendor that

develops programs and sell them to many organizations/individuals; can be standard customizable.

– Personal Application Software examples: Microsoft Excel, Word or PowerPoint

• Contract application software– Specific software programs developed for a particular

company by a vendor.

• Proprietary application software– Software that addresses a specific or unique business need

for a company/individual; may be developed in-house or may be commissioned from a software vendor.

MIS 315-05

21

Off-the-shelf application software

MIS 315-05

22

TG2.3 Application Software

• Package– A commonly used term for a computer program (or group

of programs) that have been developed by a vendor and is available for purchase in a prepackaged form.

– Example: Microsoft Office, Adobe Suite . . .

• Chapter 10 discusses the process or methodology involved in acquiring application software.

MIS 315-05

23

TG2.4 Software Issues

• Software defects– Beta vs Released

• Software evaluation and selection– SDLC … Chapter 10

• Software licensing– Copyrights … Chapter 3

• Open systems – Computing products that work together.

Apple vs Microsoft ?

• Open source software

• Software-as-a-Service

MIS 315-05

24

Software evaluation and selection

MIS 315-05

25

TG2.4 Software Issues (continued)

• Open source software– Software whose source code is available at no cost to

developers and users. Open source is not Freeware or Shareware.• Freeware is copyrighted software that is made available

free of charge• Shareware typically does not provide access to

underlying source code. (ie pre-complied code)– Open Source is copyrighted and distributed with license

terms ensuring that the source code will always be available.– Communities of developers. Linux, Apache, Open Office

• Software-as-a-Service (SaaS)– Vendor hosts the application.– Google Maps, Gapminder …

MIS 315-05

26

http://www.gapminder.org/

• The initial activity was to continue development of the Trendalyzer software. This software unveils the beauty of statistical time series by converting boring numbers into enjoyable, animated and interactive graphics.

• The current beta version of Trendalyzer is available since March 2006 as Gapminder World, a web-service displaying a few time series of development statistics for all countries www.gapminder.org/world .

• In March 2006 Google acquired Trendalyzer from Gapminder Foundation and the team of developers that worked for Gapminder has joined Google in California since April 2007.

MIS 315-05

27

Programming and Database Handout

MIS 315-05

28

TG2.5 Programming Languages

• First generation language– The lowest level programming language; composed of binary digits;

typically the only programming language understood by a CPU.

• Second generation language– more user friendly than first generation language; uses mnemonics for

people to use, such as ADD, SUB, MOV.

• Third generation language – requires the programmer to specify, step-by-step, exactly how the

computer must accomplish a task. Examples: C, Basic, FORTRAN.

• Fourth generation language– allows the user to specify the desired result without having to specify

step-by-step procedures. Examples: SAS, SPSS, APL

• Visual programming language– uses a graphical environment with mouse; icons and symbols on the

screen, or pull-down menus to make programming easier. Example: Visual Basic.

MIS 315-05

29

Object-Oriented Languages

• Object-Oriented Languages: Programming language that encapsulate a small amount of data with instructions about what to do with data.– Methods. the instructions about what to do with

encapsulated data objects.– Object. the combination of a small amount of data with the

data. – Encapsulation. the process of creating an object.– Reusability feature. – Feature of object-oriented languages that allows classes

created for one purpose to be used in a different object-oriented program if desired.

MIS 315-05

30

Hypertext Markup Language and Extensible Markup Language

• Hypertext– An approach to data management in which data are stored in a network

of nodes connected by links and are accessed through interactive browsing.

• Hyperlinks– The links that connect data nodes in hypertext.

• Hypertext document– The combination of nodes, links, and supporting indexes for any

particular topic in hypertext.

• Hypertext markup language (HTML)– The standard programming language used on the Web to create and

recognize hypertext documents.

• Extensible markup language (XML)– A programming language designed to improve the functionality of web

documents by providing more flexible and adaptable data identification.

MIS 315-05

31

Comparison of HTML and XML