MIS - CHAPTER 5

Page swapping

-"pages" -program parts of equal size that the OS swaps between RAM and the disk

First Generation

-1940s -Machine languages -Difficult to learn and use -Long instructions -Machine dependent -Inefficient tools for code writing

Second Generation

-1950s -Assembly languages -Shorter codes than machine language -Machine dependent -Inefficient tools for code writing

Third Generation

-1950s -English-like -Problem oriented -Easier to learn and use -considered "procedural" because the programmer has to detail a logical procedure that solves a problem at hand -reduced the programmer's time spent producing code

Fourth Generation

-1980s -More English-like -Many preprogrammed functions -Includes data management features -Easy to learn and use -1990s to 2000s -object-oriented programming -visual programming tools -makes application development even easier -significantly less procedural than 3GLs -with this commands, the programmer often only needs to type what is to be done, but doesn't need to specify how the procedure accomplishes the task -speed up the programming process

Human Language

-Future -Use natural language -No need to learn new syntax

Spreadsheets

-MS excel -no longer limit users to entering numbers and performing basic arithmetic calculations -include a long list of complex, mathematical, statistical, financial and other functions that users can integrate into analysis models -also provide a large array of preformatted charts from which the user can select for presentation purposes

Presentations

-MS powerpoint -enable professionals and salespeople to quickly develop impressive presentations -one does not need to be a graphics expert, because the tools provide wide selections of font types and sizes and allow users to embed almost any art that they find (with permission) or have created in graphics programs -animations, sound and video clips can be integrate -slideshows that can be posted to run on the web as videocasts

Project management tools

-MS project, Open Workbench -help managers of any type of project; such as building construction, product development and software development; to plan projects and track their progress -alerts planners when they enter illogical information, such as scheduling a worker to work 120 hours in one week and when tasks violate interdependencies

Desktop publishing ttols

-MS publisher, Adobe FrameMakers, Corel Ventura -enable both expert and novice to easily create professional looking pamphlets, newsletters, cards, calendars and many other items for publication on paper or as web pages

Linux

-OS grown in popularity -based on UNIX -an operating system developed by AT&T Bell Labs in 1969 -to run on midrange computers and for 10 years was distributed free of charge

Memory allocation

-RAM: where data and program code must reside before being executed -an entire application and all the data it processes reside in RAM until the processing ends -when many applications are open concurrently, or when applications and data pools exceed the computer's RAM capacity, the OS may use virtual memory

Hypermedia

-a feature that enables a user to access additional information by clicking on selected text or graphics -the Web's most essential ingredient -when first conceived, the concept was limited to text and was called "hypertext" -very common, used widely on software stores on CDs, and essential to web-based documents as well as documents, charts and presentations created using productivity tools -enables linking text, pictures, sounds, animations and video -its features are enabled by web page authoring tools -also part of other applications, such as some word processors and presentation tools

User interface

-a graphical user interface (GUI) makes the use of the computer intuitive and easier to learn -the interface takes the form of easy-to-understand frames, icons, and menus -users find it helpful to have most of the interface features identical regardless of the application they use

Multimedia

-a powerful means of communicating, because it does not limit the method of communication -a natural extension of the computer's capabilities, it provides flexibility that lets people work the way they think, integrating all types and forms of information -tightly associated with hypermedia, because it often uses embedded links

Source code

-a program in a high-level language before being compiled -can modified by anyone who knows the programming language in which it was written; modifying object code is very difficult

Software

-a series of instructions to a computer to execute any and all processes, such as displaying text, mathematically manipulating numbers, or copying or deleting documents -executed not only on computers, but in every device that uses microprocessors, such as motor vehicles, digital cameras and mobile phones

.NET

-a software that supports building and linking applications that can "talk to each other" on the internet and enable web browsers to invoke information resources such as databases -microsoft: enables businesses to "quickly build, deploy, manage, and use connected, security-enhanced web services"

Graphical user interface (GUI)

-a user interface which displays images and pictures that allows a computer user to interact with a computer easily -elements: windows, icons, scroll boxes, and other graphical images that help the user interact with the program with minimal effort

Permissive model

-allows anyone to use, modify and make the software into a product that can be sold or licensed for profit -Berkeley software distribution (BSD) UNIX operating system

Productivity tools

-applications that help employees in their routine office work -word processors, spreadsheets, presentation tools, file and database management software, graphic programs, desktop publishing tools and project management applications, web browsers -desktop productivity tools -developed to support home and office users on their personal computers

Virtual reality (VR)

-applications that mimic sensory reality using software -create the illusion of experiencing situations through simulated sight, hearing and touch, such as flying in an airplane or forging a piece of hot metal -includes goggles, gloves, earphones, and sometimes a moving base on which the user stands; all of these devices sense movement, respond to signals, and provide feedback to the user -business applications can decrease the cost of planning buildings, machines and vehicles -already help marketing efforts to lure buyers to try new products -has been implemented on the web; evolved from use on corporate intranets to public gatherings and other purposes

Objects

-created by programmers instead of a large, complex, tightly intertwined programs -developed in standard ways and have standard behaviors and interfaces

Data members

-data elements in the object -they might be records, whole files or another type of data structure -have attributes that define the nature of the data, such as SSS number, last name and hourly rate

Smalltalk

-developed by Xerox -an early object-oriented programming language -one of its earliest uses was to develop GUIs

File management and data management tools

-enable the creation and manipulation of local or shared databases -microsoft access: relatively easy to learn and create simple databases -often include features that professional developers can use to create more complex databases

System software

-enables application software to run on a computer, and manages the interaction between the CPU, memory, storage, input/output devices, and other computer components -includes programs that are designed to carry out general routine operations, such as the interface between user and computer, loading a file, copying a file or deleting a file, as well as managing memory resources and operating peripheral equipment such as monitors and printers -purpose: to manage computer resources and perform routine tasks that are not specific to any application -developed to work in partnership with as many applications as possible

Runtime errors

-execution errors -errors that occur while your program runs

Applications

-executives: productivity tools -a program or group of programs that are designed for users to accomplish a specific task -can also be software that lets nonprogrammers develop such programs

Programming languages

-higher level -enable the use of English-like statements to accomplish a goal, and these statements are translated by special software into the machine language

Programming language translators

-it transforms the instructions prepared by programmers in a programming language into a form that can be interpreted and executed by a computer system -can be used to find syntactic errors while testing code

Virtual memory

-lets the user proceed as if significantly more RAM were available than really exists -uses the hard disk as an extension of RAM -enables concurrent use of many and large programs without need to purchase more RAM, which is significantly more expensive than disk memory

Stability

-one of the most important qualities of an OS -does not cause the computer to freeze or produce error messages -expected to continue to function even if the user makes a mistake, in which case it should gracefully notify the user what happened and give an opportunity to resolve the problem, rather than stop functioning

Traditional programming

-programmers receive specifications of how a program should process data and how it should interact with users, and then they write code -data and the operations to manipulate the data are kept separate from each other

Graphics

-programs make it easy to create intricate images and manipulate digital photographs -often used to create graphics to be place on web pages -Adobe's illustrator and photoshop, Corel paint shop, and MGI PhotoSuite, IrfanView and Gimp

Groupware

-programs that enable workers to collaborate in real time over the Web -they not only eliminate the need to travel and sit in the same physical room but also facilitate expression of ideas by demonstrating them through the combination of text, images, drawings, sound, animation and video

General-purpose application software

-programs that serve varied purposes, such as developing decision-making tools or creating documents -spreadsheets and word processors -available as packaged software; that is, they come ready to install from an external storage medium such as a CD or a file downloaded from a vendor's website -not always so readily available

System management

-provided service by the operating systems -refers to the efficient allocation of hardware resources to applications and includes tasks such as prompting the user for certain actions, allocating RAM locations for software and data, instructing the CPU to run or stop, allocating CPU time to different programs running at the same time, and instructing co-processors and peripheral equipment

Open source software

-some programmers freely contribute to the development of a growing number of computer programs not for profit -its developers can obtain the source code free of charge, usually on the web -anyone who can contribute features or fix things is invited to do so -anyone who wishes to download the latest version can do so free of charge -can be developed by a random group of programmers, rather than by a single company; share an application's basic code, find its weaknesses, debug it, and contribute new pieces -advantages: fewer bugs -motive: not monetary, but rather the satisfaction of solving programming problems and the recognition of one's contribution -collaborates via the internet -disadvantage: development and support depend on the continued effort of an army of volunteers

Member functions (methods)

-the code elements of the object -these procedures operate on the data, such as calculating an employee's gross pay for the week

Propriety software

-the great majority of business and individual software developed and sold for profit -its developers do not make the source code of their software public -the developer retains the rights to the software -you do not actually own the copies of applications that you purchase; only licenses

Machine language

-the language made up of binary-coded instructions that is used directly by the computer -writing programs in this language requires a programmer to literally create long strings of ones and zeroes to represent different characters and symbols, work that is no longer required thanks to programming language s and other software development tools

Programming

-the process of writing programs -"writing code" -"software engineering"

Operating system (OS)

-the single most important programs that runs on a computers and the most important type of system software -without it, no application can run on a computer -developed for a certain microprocessor or multiple microprocessors -must address technical details such as CPU circuitry and memory addresses -usually developed with the aid of low-level programming languages, such as assembly languages, or with a languages that can access low-level machine functions, such as C -"traffic cop", "boss" of computer resources -charged with control functions such as optimally allocating memory locations for an application program, copying the application from an external storage medium into memory, passing control to the CPU for execution of program instructions, and sending processing results to output devices -"platforms": they are the platform on which all other applications "ride" when interacting with the hardware

Visual Programming Language

-to accelerate programmers' work -Microsoft visual basic, Borland delphi, Micro focus COBOL, ASNA visual RPG, and Visual C++ -lets programmers create field windows, scroll-down menus, click buttons, and other objects by simply choosing the proper icon from a palette -then use a flexible tool to shape and color these objects

Interpreter

-translate each program statement and execute it -checks one statement at a time -if the first statement is free of syntactic errors, it interprets the statement into object code and makes the computer execute it -if the statement is erroneous, the interpreter issues an error message

Compilers

-translate the higher-level code into an equivalent machine language code, but do not execute the code; the translated code must be run to check for programming errors -scans the entire source code, looking for errors in the form (syntax) of the code -if it finds an error, it does not create the object code; instead, it generates an error message or a list of error messages

Increasing services from OSs

-trend: to incorporate more and more services that used to be provided by separate software -services: database management, networking and security

word processors, electronic spreadsheets, web browsers, games, project management tools, collaborative work programs, database management programs, presentation programs

-types of productivity tools -software that runs on computers and enables workers to produce more products and services in a given amount of time

Object-oriented programming (OOP) languages

-use modular approach, which offers two great advantages: ease of maintenance and efficiency in applications development -operations are linked to the data -primary emphasis: not on the procedure for performing a task, but on the objects involved in the task -software developers treat objects as parts, or standardized modules that work together and can be used and reused -makes creating programs easier for nonprogrammers -Smalltalk, C++, Object pascal, and Java -some of its language are designed specifically for use in developing graphical user interfaces (GUIs)

Word processors

-used mainly to type letters, articles, and other text documents -they also automate otherwise laborious tasks such as creating tables of contents and indexes -MS word, Corel WordPerfect, Lotus WordPro

Application program interfaces (APIs)

-used when the application developers write code for the operating system on which the application will run -software included in the operating system -make it easy to develop an application

1. The application is executed immediately because there is no need to compile the code 2. Most users do not have the compiler for the source code 3. The vendor does not wish buyers to modify the code

-when you purchase an application, computer game or business program, you purchase a compiled version of the code, that is, the object code -there are three reasons

Current operating systems

-while specific operating systems exist for supercomputers, mainframe computers, midrange computers and handheld computers, most people use a PC operating system -some operating systems are designed especially for computers used as servers in networks

Software suite

A group of software programs sold as a single unit. Usually the programs have common features that make it easy to integrate and share data.

Java

A popular object-oriented language designed to be platform independent, that is, to run on any computer regardless of the CPU or operating system.

Packaged software

A software program written by a third-party vendor for the needs of many different users and organizations.

1. Easy of learning the language 2. Ease of programming 3. Significantly shorter code 4. Ease of debugging 5. Ease of maintenance

Advantages of Higher-level Programming

Immersion

An individual senses that he or she is surrounded by the simulated environment.

Visual Basic

Another popular language that enables the programmer to use graphical objects, but does not fulfill all the requirements of a true OOP language.

Link

Any text or icon that can be clicked to jump to another place in a document or open a new document, whether on the web or not.

Mashups

Applications that incorporate data from multiple providers into a new application.

C++

Become the major commercial OOP language because it combines traditional C programming with object-oriented capabilities.

1. Business needs 2. Organizational culture needs 3. The need to interface with other systems 4. Performance issues

Considerations for packaged software

1. Less control over hardware 2. Less efficient memory use 3. Program runs more slowly

Disadvantages of Higher-Level Programming

Application software

Enables users to complete a particular application or task, such as word processing, investment analysis, data manipulation or project management.

1. Multimedia in Education and Research 2. Multimedia in Training 3. Multimedia in Business

Examples of the uses of multimedia

Avatars

Graphic representations of users of virtual worlds.

The modified copies may be sold without violating intellectual property laws such as patents and copyrights

If the program is sufficiently modified?

Interaction

Lets individuals simulate change in the environment by moving their hands or fingers.

1. Permissive model 2. General public license (GPL)

Licensing of software comes in several models

Applets

Main advantage of Java, JavaScript, and J2EE is that the code produced can be executed well regardless of the operating system that the computer uses.

1. Requires less code than other languages 2. Requires less time than programming in other languages 3. Enhances program modularity and reusability 4. Makes code maintenance easier 5. Enhances ability to create user-friendly interface 6. Is appropriate for graphic-and sound-enhanced applications

OOPS advantages over procedural languages

1. The user interacts with the user interface using menus, icons, and commands provided by the application 2. The application converts some of the user's input into commands the OS understands 3. The OS commands the CPU to carry out the operation 4. The OS ensures that applications can use the CPU, memory, input and output devices, and the file system

OS's position in the logical operation of computer

1. User interface 2. Memory allocation 3. Plug and play 4. Increasing services from OSs 5. Current operating systems

Operating system functions

-recognizing input from the keyboard and mouse -sending output to the computer display -keeping track of files and directories (group of files) on disks -sending documents to the printer

Operating systems perform basic tasks

General public license (GPL)

Permits anyone to use, modify, and make applications with the code, but not to use it in proprietary products for sale or licensing.

Software maintenance

Primarily involves modifying programs to meet new business needs but also debugging of errors that were not detected when testing the developed code

Application-specific software

Programs designed to perform specific jobs, such as calculating and executing a company's payroll

Multimedia software

Programs that can handle many different types of data.

Make the work of people more productive

Purpose of all business software?

3D Geographic software

Similar to virtual reality, used to develop three-dimensional models of geographical locations; essentially is a Geographic Information System.

Web page authoring tools

Software that is used to design and present web pages.

File system

Software that stores, organizes and retrieves files.

1. First Generation 2. Second Generation 3. Third Generation 4. Fourth Generation 5. Human Language

The evolution of programming languages

1. Immersion 2. Interaction

The most sophisticated VR devices provide two important elements

Object code

The output of the compiler after it translates the program

Drive

The software that enables the OS to control a device, either one installed inside the computer box (second video card) or an external drive such as a flash memory drive.

Swap space

The space on disk used as memory

1. Application software 2. System software

Two major categories of software

1. Compilers 2 Interpreters

Two types of Programming language translators

Software development tools

even easier to use because they require practically no knowledge of programming languages to develop software

Debugging

locating and fixing programming errors

Assembly lanaguages

made programming somewhat easier because they aggregated common commands into "words", although many of the "words" are not English-like

Plug and play

technology that allows a hardware component to be attached to a computer so that it is automatically configured by the operating system, without user intervention