1.  2001 Deitel & Associates, Inc. All rights reserved. 1 Chapter 1 – Introduction to Computers, the Internet and the Web Outline 1.1Introduction 1.2The Future of Computing 1.3e-Business and e-Commerce 1.4What is a Computer? 1.5Types of Programming Languages 1.6Other High-Level Languages 1.7Structured Programming 1.8History of the Internet 1.9Personal Computing, Distributed Computing and Client/Server Computing 1.10History of the World Wide Web 1.11Hardware Trends 1.12The Key Software Trend: Object Technology 1.13JavaScript: Object-Based Scripting for the Web 1.14Browser Portability 1.15Evolution of the How to Program Series: C and C++

2.  2001 Deitel & Associates, Inc. All rights reserved. 2 Chapter 1 – Introduction to Computers, the Internet and the Web Outline 1.16Java and Java How to Program 1.17Internet and World Wide Web How to Program 1.18e-Business and e-Commerce How to Program 1.19Dynamic HTML

3.  2001 Deitel & Associates, Inc. All rights reserved. 3 1.1 Introduction We will learn –Structured programming and proper programming techniques This course is appropriate for –Novices with little or no programming experience –Experienced professionals building substantial information systems

4.  2001 Deitel & Associates, Inc. All rights reserved. 4 1.2 The Future of Computing Future of Computers –Use increasing dramatically –Costs decreasing –Explosion of Internet and World Wide Web Multimedia content Increasing bandwidth Magazines and books already going online Easy international communication –Could replace TV, radio and phone –Helping the disabled

5.  2001 Deitel & Associates, Inc. All rights reserved. 5 1.3 e-Business and e-Commerce e-Business –Provides products and services 24 hours a day –Provides unlimited inventory –Allows consumer to comparison shop –Essential to business success –Replacing “brick and mortar” stores –Personalize user’s experience New business models introduced by Web –eBay Online auctions –Priceline.com Customers name own price

6.  2001 Deitel & Associates, Inc. All rights reserved. 6 1.3 e-Business and e-Commerce Consequences of Internet and Web –Privacy invasion One of the risks of Internet Personal information on the Web Tracking of Web movement Credit card security –Piracy of intellectual property Copyright infringement MP3

7.  2001 Deitel & Associates, Inc. All rights reserved. 7 1.4 What is a Computer? Computer –Device capable of performing computations and making logical decisions –Computers process data under the control of sets of instructions called computer programs Hardware –Various devices comprising a computer –Keyboard, screen, mouse, disks, memory, CD-ROM, and processing units Software –Programs that run on a computer

8.  2001 Deitel & Associates, Inc. All rights reserved. 8 1.5 Types of Programming Languages Three types of programming languages 1.Machine languages Strings of numbers giving machine specific instructions Example: +1300042774 +1400593419 +1200274027 2.Assembly languages English-like abbreviations representing elementary computer operations (translated via assemblers) Example: LOAD BASEPAY ADD OVERPAY STORE GROSSPAY

9.  2001 Deitel & Associates, Inc. All rights reserved. 9 1.5 Types of Programming Languages 3.High-level languages Codes similar to everyday English Use mathematical notations (translated via compilers) Example: grossPay = basePay + overTimePay

10.  2001 Deitel & Associates, Inc. All rights reserved. 10 1.6 Other High-level Languages Other high-level languages –FORTRAN Used for scientific and engineering applications –COBOL Used to manipulate large amounts of data –Pascal Intended for academic use

11.  2001 Deitel & Associates, Inc. All rights reserved. 11 1.7 Structured Programming Structured programming –Disciplined approach to writing programs –Clear, easy to test and debug and easy to modify Multitasking –Specifying that many activities run in parallel

12.  2001 Deitel & Associates, Inc. All rights reserved. 12 1.8 History of the Internet The Internet enables –Quick and easy communication via e-mail –International networking of computers Packet switching –The transfer of digital data via small packets –Allows multiple users to send and receive data simultaneously No centralized control –If one part of the Internet fails, other parts can still operate Bandwidth –Information carrying capacity of communications lines

13.  2001 Deitel & Associates, Inc. All rights reserved. 13 1.9 Personal Computing, Distributed Computing, and Client/Server Computing Personal computers –Economical enough for individual Distributed computing –Computing distributed over networks Client/server computing –Sharing of information across computer networks between file servers and clients (personal computers)

14.  2001 Deitel & Associates, Inc. All rights reserved. 14 1.10 History of the World Wide Web WWW –Allows computer users to locate and view multimedia- based documents –Introduced in 1990 by Tim Berners-Lee Internet today –Mixes computing and communications technologies –Makes information constantly and instantly available to anyone with a connection

15.  2001 Deitel & Associates, Inc. All rights reserved. 15 1.11 Hardware Trends Improving technologies –Internet community thrives on improvements of Hardware Software Communications –Cost of products and services Consistently dropping over the decades –Computer capacity and speed Doubles every two years (on average) –Microprocessor chip Laid groundwork in late 1970s and 1980s for productivity improvements of the 1990s

16.  2001 Deitel & Associates, Inc. All rights reserved. 16 1.12 The Key Software Trend: Object Technology Objects –Reusable software components that model items in the real world –Meaningful software units Date objects, time objects, paycheck objects, invoice objects, audio objects, video objects, file objects, record objects, etc. Any noun can be represented as an object –More understandable, better organized, and easier to maintain than procedural programming –Favor modularity

17.  2001 Deitel & Associates, Inc. All rights reserved. 17 1.13 JavaScript: Object-Based Scripting for the Web JavaScript –Attractive package for advancing level of programming language education –Object-based language –Supports proper software engineering techniques –Free for download in today’s most popular Web browsers Attractive to colleges Bug fixes and new versions easily obtained –Powerful scripting language Portable Programs execute interpretively on client machines

18.  2001 Deitel & Associates, Inc. All rights reserved. 18 1.14 Browser Portability Browser portability –Great challenge Great diversity of client browsers in use Many different platforms also in use Difficult to –Know capabilities and features of all browsers and platforms in use –Find correct mix between absolute portability, complexity and usability of features

19.  2001 Deitel & Associates, Inc. All rights reserved. 19 1.15Evolution of the How to Program Series: C++ and C++ C –Wasn’t used for teaching because of Pascal Used in business and in operating systems C How to Program began teaching C to university students –Portable across many platforms C++ –Extension of C –Provides capabilities for object-oriented programming –Very widely used in industry Lead to writing of C++ How to Program

20.  2001 Deitel & Associates, Inc. All rights reserved. 20 1.16 Java and Java How to Program Java is used to –Create Web pages with dynamic and interactive content –Develop large-scale enterprise applications –Enhance the functionality of Web servers –Provide applications for consumer devices (such as cell phones, pagers and personal digital assistants) Java How to Program –Closely followed the development of Java by Sun –Teaches first-year programming students the essentials of graphics, images, animation, audio, video, database, networking, multithreading and collaborative computing

21.  2001 Deitel & Associates, Inc. All rights reserved. 21 1.17 Internet and World Wide Web How to Program Internet and World Wide Web How to Program –Followed the Internet boom –Focuses on enhanced capabilities of the Web Still provides a solid treatment of programming principles

22.  2001 Deitel & Associates, Inc. All rights reserved. 22 1.18 e-Business and e-Commerce How to Program e-Business and e-Commerce How to Program: –Step beyond Internet and World Wide Web How to Program –Explicitly teaches programming for e-Business and e- commerce –Firm grounding for conducting business on-line –Computer programming and basic principles of computer science –JavaScript primary programming language

23.  2001 Deitel & Associates, Inc. All rights reserved. 23 1.19 Dynamic HTML DHTML –Two versions Microsoft Netscape –Consists of number of technologies freely available for download –Used for developing high-performance, Web-based applications Much of application’s work performed directly on client rather then on server or Internet