Discovering Computers Fundamentals 2012 Edition Your Interactive Guide

Discovering Computers Fundamentals, 2012 Edition Your Interactive Guide to the Digital World

Objectives Overview Discuss the importance of project management, feasibility assessment, documentation, and data and information gathering techniques Discuss the purpose of each system development phase Differentiate between lowlevel languages and procedural languages Identify the benefits of object-oriented programming languages and program development tools See Page 417 for Detailed Objectives Discovering Computers Fundamentals, 2012 Edition Chapter 11 2

Objectives Overview List other programming languages and other program development tools Describe various ways to develop Web pages List the six program development steps Explain the basic control structures used in designing solutions to programming problems See Page 417 for Detailed Objectives Discovering Computers Fundamentals, 2012 Edition Chapter 11 3

System Development System development is a set of activities used to build an information system A system is a set of components that interact to achieve a common goal Page 418 An information system (IS) is a System development collection of activities are grouped hardware, software, into phases, and is data, people, and called the system procedures that work development life together to produce cycle (SDLC) quality information Discovering Computers Fundamentals, 2012 Edition Chapter 11 4

System Development Page 418 Figure 11 -1 Discovering Computers Fundamentals, 2012 Edition Chapter 11 5

System Development • System development should follow three general guidelines: Group activities or tasks into phases Involve users Define standards Page 419 Discovering Computers Fundamentals, 2012 Edition Chapter 11 6

System Development • System development should involve representatives from each department in which the proposed system will be used Page 419 Figure 11 -2 Discovering Computers Fundamentals, 2012 Edition Chapter 11 7

System Development • Project management is the process of planning, scheduling, and then controlling the activities during system development • To plan and schedule a project efficiently, the project leader identifies: Page 420 Project scope Required activities Time estimates for each activity Cost estimates for each activity Order of activities Activities that can take place at the same time Discovering Computers Fundamentals, 2012 Edition Chapter 11 8

System Development A popular tool used to plan and schedule the time relationships among project activities is a Gantt chart Pages 420 - 421 Figure 11 -3 a Discovering Computers Fundamentals, 2012 Edition Chapter 11 9

System Development A PERT chart also can be used for planning and scheduling time Pages 420 - 421 Figure 11 -3 b Discovering Computers Fundamentals, 2012 Edition Chapter 11 10

System Development • Feasibility is a measure of how suitable the development of a system will be to the organization Operational feasibility Page 421 Schedule feasibility Technical feasibility Discovering Computers Fundamentals, 2012 Edition Chapter 11 Economic feasibility 11

System Development • Documentation is the collection and summarization of data and information and includes: – Reports – Diagrams – Programs – Other information generated during system development Page 422 Discovering Computers Fundamentals, 2012 Edition Chapter 11 12

System Development • During system development, members of the project team gather data and information using several techniques Review documentation Observe Survey Interview JAD Sessions Research Pages 422 - 423 Figure 11 -4 Discovering Computers Fundamentals, 2012 Edition Chapter 11 13

System Development A user may request a new or modified system Organizations may want to improve hardware, software, or other technology Situations beyond an organization’s control might require a change Management might mandate a change A user may request a new or modified information system using a request for system services or a project request Page 423 Discovering Computers Fundamentals, 2012 Edition Chapter 11 14

System Development Page 424 Figure 11 -5 Discovering Computers Fundamentals, 2012 Edition Chapter 11 15

System Development • The planning phase for a project begins when the steering committee receives a project request • Four major activities are performed: Review and approve the project requests Page 425 Prioritize the project requests Allocate resources Discovering Computers Fundamentals, 2012 Edition Chapter 11 Form a project development team 16

System Development • The analysis phase consists of two major activities: Conduct a preliminary investigation Perform detailed analysis • Determines and defines the exact nature of the problem or improvement • Interview the user who submitted the request • Study how the current system works • Determine the users’ wants, needs, and requirements • Recommend a solution Pages 425 - 427 Discovering Computers Fundamentals, 2012 Edition Chapter 11 17

System Development Page 426 Figure 11 -6 Discovering Computers Fundamentals, 2012 Edition Chapter 11 18

System Development • The system proposal assesses the feasibility of each alternative solution • The steering committee discusses the system proposal and decides which alternative to pursue Packaged software Pages 427 - 428 Custom software Discovering Computers Fundamentals, 2012 Edition Chapter 11 Outsourcing 19

System Development • The design phase consists of two major activities Acquire hardware and software Page 428 Develop all of the details of the new or modified information system Discovering Computers Fundamentals, 2012 Edition Chapter 11 20

System Development • To acquire the necessary hardware and software: • Use research techniques such as e-zines Identify technical specifications Pages 428 - 430 Solicit vendor proposals • RFQ, RFP, or RFI is sent to potential vendors or VARs • Various techniques are used to determine the best proposal Make a decision • Systems analyst makes recommendation to steering committee Test and evaluate vendor proposals Discovering Computers Fundamentals, 2012 Edition Chapter 11 21

System Development • The next step is to develop detailed design specifications – Sometimes called a physical design Databas e design Page 430 Input and output design Discovering Computers Fundamentals, 2012 Edition Chapter 11 Program design 22

System Development • Systems analysts typically develop two types of designs for each input and output Mockup Pages 430 - 431 Figures 11 -8 – 11 -9 Layout chart Discovering Computers Fundamentals, 2012 Edition Chapter 11 23

System Development • A prototype (proof of concept) is a working model of the proposed system – Prototypes have inadequate or missing documentation – Users tend to embrace the prototype as a final system – Should not eliminate or replace activities Page 431 Discovering Computers Fundamentals, 2012 Edition Chapter 11 24

System Development • Computer-aided software engineering (CASE) tools are designed to support one or more activities of system development Page 432 Figure 11 -10 Discovering Computers Fundamentals, 2012 Edition Chapter 11 25

System Development • The purpose of the implementation phase is to construct the new or modified system and then deliver it Develop programs Page 432 Install and test the new system Train users Discovering Computers Fundamentals, 2012 Edition Chapter 11 Convert to the new system 26

System Development • Various tests should be performed on the new system Unit test • Verifies that each individual program or object works by itself Page 433 Systems test • Verifies that all programs in an application work together properly Integration test Acceptance test • Verifies that an application works with other applications • Checks the new system to ensure that it works with actual data Discovering Computers Fundamentals, 2012 Edition Chapter 11 27

System Development • Training involves showing users exactly how they will use the new hardware and software in the system – One-on-one sessions – Classroom-style lectures – Web-based training Page 433 Figure 11 -11 Discovering Computers Fundamentals, 2012 Edition Chapter 11 28

System Development • One or more of four conversion strategies can be used to change from the old system to the new system – Direct conversion – Parallel conversion – Phased conversion – Pilot conversion Pages 433 - 434 Discovering Computers Fundamentals, 2012 Edition Chapter 11 29

System Development • The purpose of the operation, support, and security phase is to provide ongoing assistance for an information system and its users after the system is implemented Perform maintenance activities Page 434 Monitor system performance Discovering Computers Fundamentals, 2012 Edition Chapter 11 Assess system security 30

System Development • A computer security plan should do the following: Identify all information assets of an organization Page 434 Identify all security risks that may cause an information asset loss For each risk, identify the safeguards that exist to detect, prevent, and recover from a loss Discovering Computers Fundamentals, 2012 Edition Chapter 11 31

Video: Create a Hidden Operating System Discovering Computers Fundamentals, 2012 Edition Chapter 11 32

Programming Languages and Program Development Tools • A computer program is a series of instructions that directs a computer to perform tasks – Created by a programmer using a programming language Pages 435 - 436 Figure 11 -12 Discovering Computers Fundamentals, 2012 Edition Chapter 11 33

Programming Languages and Program Development Tools • Machine language is the first generation of programming languages • Only language the computer directly recognizes Page 436 Figure 11 -13 Discovering Computers Fundamentals, 2012 Edition Chapter 11 34

Programming Languages and Program Development Tools • Assembly language is the second generation of programming languages • Programmer writes instructions using symbolic instruction codes • A source program contains the code to be converted to machine language Page 437 Figure 11 -14 Discovering Computers Fundamentals, 2012 Edition Chapter 11 35

Programming Languages and Program Development Tools • In a procedural language, the programmer writes instructions that tell the computer what to accomplish and how to do it – Third-generation language (3 GL) A compiler translates an entire program before executing it Page 438 An interpreter converts and executes one code statement at a time Discovering Computers Fundamentals, 2012 Edition Chapter 11 36

Programming Languages and Program Development Tools Pages 438 – 439 Figures 11 -15 – 11 -16 Discovering Computers Fundamentals, 2012 Edition Chapter 11 37

Programming Languages and Program Development Tools • The C programming language is used to write many of today’s programs Page 439 Figure 11 -17 Discovering Computers Fundamentals, 2012 Edition Chapter 11 38

Programming Languages and Program Development Tools • COBOL (COmmon Business-Oriented Language) is designed for business applications, but easy to read because of the English-like statements Page 440 Figure 11 -18 Discovering Computers Fundamentals, 2012 Edition Chapter 11 39

Programming Languages and Program Development Tools • An object-oriented programming (OOP) language allows programmers the ability to reuse and modify existing objects • Other advantages include: Page 440 Objects can be reused Programmers create applications faster Work well in a RAD environment Most program development tools are IDEs Discovering Computers Fundamentals, 2012 Edition Chapter 11 40

Programming Languages and Program Development Tools • Java is an object-oriented programming language developed by Sun Microsystems • The Just-in-time (JIT) compiler to convert the bytecode into machine-dependent code Pages 440 - 441 Figure 11 -19 Discovering Computers Fundamentals, 2012 Edition Chapter 11 41

Programming Languages and Program Development Tools • The Microsoft. NET Framework allows almost any type of program to run on the Internet or an internal business network, as well as computers and mobile devices Page 441 Discovering Computers Fundamentals, 2012 Edition Chapter 11 42

Programming Languages and Program Development Tools • C++ is an extension of the C programming language – Additional features for working with objects, classes, events, and other object-oriented concepts • C# is based on C++ and was developed by Microsoft • C# combines the benefits of an object-oriented language with the benefits of a functional language Page 441 Discovering Computers Fundamentals, 2012 Edition Chapter 11 43

Programming Languages and Program Development Tools Visual Studio is Microsoft’s suite of program development tools Visual Basic is based on the BASIC programming language Pages 441 - 443 Visual C# combines the programming Visual C++ is based elements of C++ with an easier, on C++ rapid-development environment Discovering Computers Fundamentals, 2012 Edition Chapter 11 44

Programming Languages and Program Development Tools Pages 442 Figure 11 -20 Discovering Computers Fundamentals, 2012 Edition Chapter 11 45

Programming Languages and Program Development Tools A visual programming language is a language that uses a visual or graphical interface for creating all source code Borland’s Delphi is a powerful program development tool that is ideal for building largescale enterprise and Web applications in a RAD environment Page 443 Discovering Computers Fundamentals, 2012 Edition Chapter 11 46

Programming Languages and Program Development Tools • Power. Builder is a powerful program development RAD tool • Best suited for Web-based, . NET, and large-scale enterprise object-oriented applications Page 443 Discovering Computers Fundamentals, 2012 Edition Chapter 11 47

Programming Languages and Program Development Tools • A 4 GL (fourth-generation language) is a nonprocedural language that enables users and programmers to access data in a database – One popular 4 GL is SQL Page 443 Figure 11 -21 Discovering Computers Fundamentals, 2012 Edition Chapter 11 48

Programming Languages and Program Development Tools • Classic programming languages include: Page 444 Figure 11 -22 Ada ALGOL APL BASIC Forth FORTRAN Hyper. Talk LISP Logo Modula-2 Pascal PILOT PL/1 Prolog RPG Smalltalk Discovering Computers Fundamentals, 2012 Edition Chapter 11 49

Programming Languages and Program Development Tools • An application generator is a program that creates source code or machine code from a specification of the required functionality – Often bundled as part of a DBMS Pages 444 - 445 Figure 11 -23 Discovering Computers Fundamentals, 2012 Edition Chapter 11 50

Programming Languages and Program Development Tools • A macro is a series of statements that instructs an application how to complete a task • You usually create the macro in one of two ways: – Record the macro with a macro recorder – Write the macro Page 445 Discovering Computers Fundamentals, 2012 Edition Chapter 11 51

Programming Languages and Program Development Tools • HTML is a special formatting language that programmers use to format documents for display on the Web • XHTML is a markup language that allows Web sites to be displayed more easily on mobile devices Page 446 Figure 11 -24 Discovering Computers Fundamentals, 2012 Edition Chapter 11 52

Programming Languages and Program Development Tools • XML allows Web developers to create customized tags and use predefined tags to display content appropriately on various devices – WML is a subset of XML and is used to design pages for microbrowsers • Two applications of XML are RSS 2. 0 and ATOM Pages 446 - 447 Discovering Computers Fundamentals, 2012 Edition Chapter 11 53

Programming Languages and Program Development Tools • Web browsers can execute short programs to add interactive elements to Web pages • To send and receive information between your computer and a Web server, these programs use the CGI (common gateway interface) Page 447 Scripts Applets Servlets Active. X controls Discovering Computers Fundamentals, 2012 Edition Chapter 11 54

Programming Languages and Program Development Tools • Programmers write scripts, applets, servlets, or Active. X controls using a variety of languages Java. Script Perl PHP Rexx Tcl VBScript Pages 447 - 448 Discovering Computers Fundamentals, 2012 Edition Chapter 11 55

Programming Languages and Program Development Tools Dynamic HTML (DHTML) allows Web developers to include more graphical interest and interactivity Ruby on Rails (Ro. R) provides technologies for developing object-oriented, databasedriven Web sites Page 448 Discovering Computers Fundamentals, 2012 Edition Chapter 11 56

Programming Languages and Program Development Tools • Web 2. 0 allows Web sites to provide a means for users to: Share personal information Allow users to modify Web site content Have application software built into the site Page 448 Discovering Computers Fundamentals, 2012 Edition Chapter 11 57

Programming Languages and Program Development Tools • Most Web 2. 0 sites use APIs – An API enables programmers to interact with an environment such as a Web site or operating system Page 448 Figure 11 -26 Discovering Computers Fundamentals, 2012 Edition Chapter 11 58

Programming Languages and Program Development Tools • Web page authoring software can create sophisticated Web pages that include images, video, audio, animation, and other effects Page 449 Dreamweaver Expression Web Flash Share. Point Designer Discovering Computers Fundamentals, 2012 Edition Chapter 11 59

Programming Languages and Program Development Tools • Multimedia authoring software allows programmers to combine text, graphics, animation, audio, and video in an interactive presentation Tool. Book Page 449 Director Discovering Computers Fundamentals, 2012 Edition Chapter 11 60

Programming Languages and Program Development Tools Page 449 Figure 11 -27 Discovering Computers Fundamentals, 2012 Edition Chapter 11 61

Program Development Cycle • Program development consists of a series of steps programmers use to build computer programs Pages 450 - 451 Figure 11 -28 Discovering Computers Fundamentals, 2012 Edition Chapter 11 62

Program Development Cycle • The sequence control structure shows one or more actions following each other in order Page 452 Figure 11 -29 Discovering Computers Fundamentals, 2012 Edition Chapter 11 63

Program Development Cycle • The selection control structure tells the program which action to take, based on a certain condition – If-then-else – Case Page 452 Figure 11 -30 Discovering Computers Fundamentals, 2012 Edition Chapter 11 64

Program Development Cycle Page 453 Figure 11 -31 Discovering Computers Fundamentals, 2012 Edition Chapter 11 65

Program Development Cycle • The repetition control structure enables a program to perform one or more actions repeatedly as long as a certain condition is met Page 453 Figures 11 -32 – 11 -33 Discovering Computers Fundamentals, 2012 Edition Chapter 11 66

Video: Electronic Arts Going Mobile Discovering Computers Fundamentals, 2012 Edition Chapter 11 67

Summary System development phases Guidelines for system development Activities that occur during system development Various programming languages and program development tools Web development and multimedia development tools Program development and the tools used in this process Page 454 Discovering Computers Fundamentals, 2012 Edition Chapter 11 68

Discovering Computers Fundamentals, 2012 Edition Your Interactive Guide to the Digital World Chapter 11 Complete