Bis Chapter4

TOPICS 1. Categories of computer software 2. Document production software 3. Graphics packages 4. Spreadsheets 5. Databases 6. Management applications of productivity software 7. Multimedia software Software for using the Internet

Software defined Software is a series of detailed instructions that control the operation of a computer system. Software exists as programs that are developed by computer programmers. Examples of software: Microsoft Windows Microsoft Office (Word, Excel, PowerPoint, Access, Outlook) Norton AntiVirus Oracle Database Daceasy accounting software, MYOB accounting software

Figure 4.1 Categories of computer software

Systems Software It manages and controls the operation of the computer system as it performs tasks on behalf of the user. Systems software consists of three basic categories: operating systems development programs e.g. Visual Basic utility programs e.g. BIOS

Operating System Operating system (OS) is a software that interacts with the hardware of the computer in order to manage and direct the computer’s resources. For most operating systems such as Microsoft DOS there is a text-based operating system. A GUI (graphical user interface) operating environment such as Windows XP.

Figure 4.2 Diagram showing the relationships between the different types of software and hardware

Graphical User Interface A Graphical user Interface (GUI) allows users to enter instructions using a mouse. The mouse is used to issue instructions using menus and icons. The term WIMP (windows, icons, mouse and pull-down menus) is often used to describe this kind of environment. Examples of operating systems using a GUI are Windows XP and some versions of UNIX.

Network operating system software The network operating system (NOS) used by an organization will provide the majority of facilities required to support workgroup computing. NOS is the software needed to operate and manage a network system. Services provided by the NOS include: A centralised storage space Security or access control features to restrict access to documents and other data by those outside the workgroup. Allow access to resources and facilities NOS are now often integrated with operating systems such as Microsoft Windows XP and UNIX. However, older systems still exist that use software such as Novell Netware in conjunction with earlier versions of Microsoft Windows.

Development Programs They a llow users to develop their own software in order to carry out processing tasks using programming languages . Example: Visual Basic for Applications – built into MS Word and Excel

Utility Programs They provide a range of tools that support the operation and management of a computer system. Programs that monitor system performance or provide security controls are examples of utility programs.

Applications Software Applications software is a set of programs that enable users to perform specific information processing activities that may be general-purpose or application-specific. General purpose applications are programs that can be used to carry out a wide range of common tasks , e.g. Microsoft Office Application specific software comprises programs intended to serve a specific purpose or carry out a clearly defined information processing task. Examples are accounting software such as MYOB, Flex-system. enterprise resource planning (ERP) software.

Categories of Programming Languages Machine Languages Use binary coded instructions 1001 1001 1100 1101 High Level Languages Use brief statements Compute X = Y + Z Markup Languages Use embedded control codes Assembler Languages Use symbolic coded instructions LOD Y ADD Z Fourth Generation Languages Use natural statements Object-Oriented Languages Define objects that contain data and actions Document.write (“Hi There”) <H1>First heading</H> <!ELEMENT Product (#Item | manuf)> SUM THE FOLLOWING NUMBERS

Development of different programming languages First generation Characteristics and advantages Early computer systems were programmed using machine language that consisted of strings of binary digits. Main disadvantages Programs were considered expensive to develop as they took extremely long periods of time to design, code and test.

Development of different programming languages Second generation Characteristics and advantages Assembly language represented an attempt to simplify the process of creating computer programs. Symbols and abbreviations were used to create sequences of instructions. An assembler or low-level language was used to translate a completed assembly language program into the machine code required by the computer.

Development of different programming languages Main disadvantages Relatively slow for certain tasks, such as those involving large-scale data processing. Remained difficult to create large or complex programs using assembly language.

Development of different programming languages Third generation Characteristics and advantages Provided a more natural means of developing programs by enabling users to create programs made up of English-like statements. Such programming languages are still in use today and are known as “high-level languages”. Languages such as COBOL, Fortran, C++ and Java allowed users to develop programs quickly and easily.

Programming Language Translation Language Translation Process Source Program Machine Language Object Program Written in BASIC, COBOL, etc. Language Translator Program Compiler Interpreter Assembler IF A := B THEN 1001101 1110101 0010110

Development of different programming languages Main disadvantage Resulting applications were sometimes slow and inefficient.

Development of different programming languages Fourth generation Characteristics and advantages A drive towards even greater ease of use resulted in the development of new programming systems designed to allow even non-technical users to develop their own applications. The focus of such tools as Microsoft Visual Basic.NET is on ease of use and the rapid development of applications. Examples of common programming tools include report generators, query languages and application generators.

Development of different programming languages Main disadvantage Some programming knowledge is still necessary.

Development of different programming languages Fifth generation Characteristics and advantages Developments in this area may result in programming systems that accept a spoken question from a user and then generate a computer program intended to produce the required information. Main disadvantage Artificial intelligence techniques are still not sufficiently developed to make this a practical reality.

Document production software One of the most common activities in a business organization is the production of documents for internal or external use. Internal documents , such as an inter-office memo, are generally used to support communications within an organization. Appearance of internal document is seldom important as the document main purpose is to convey information quickly and efficiently. External documents , such as a sales brochure, are generally used to support communications with customers, suppliers and other agencies. Appearance of an external document can have an impact on an organization’s image and reputation. Therefore a great deal of emphasis is often placed upon presentation.

Document production software (Continued) Document production technology Word processing is concerned with entering or editing text, with emphasis on the content of the document. Word processing allows the production of simple documents but gives more limited control over layout. Desktop publishing is concerned with the overall appearance of documents, placing a great deal of emphasis on features that provide control over the layout and presentation of a document. Document management involves managing documents such as company procedures, letters from customers or invoices from suppliers which are circulated to people throughout an organization.

Document production software (Continued) The distinctions between different categories of document production software have become blurred. A modern word processor will often have much of the functionality of a desktop publishing program. Many desktop publishing packages have sophisticated text editing features and no longer rely on users’ preparing the different elements of a document in advance.

Office automation systems (OAS) Office automation systems are computer-based information systems used in producing documents or organizing meetings. These systems can help to improve efficiency, reduce costs and enhance internal communications. The functions of office automation systems are commonly provided by groupware. Groupware is a category of software used to support the activities of workgroups. Groupware is software which enables information and decision making to be shared by people collaborating within and between businesses. In general, groupware applications fall within two basic categories: electronic communications systems , supporting internal and external communications and electronic meeting systems .

Electronic meeting systems Electronic meeting systems describes a category of Office Automation Systems that seeks to improve communications between individuals and groups. Examples of these systems include those that support teleconferencing, teleworking and group work.

Features of a word processor Editing Text alignment Block operations Search and replace Text formatting and style Headers and footers Mailmerge Import and export Language tools – spellchecking and grammar checking Drawing tools Tables Programming applications A macro is a sequence of instructions that can be used to automate complex or repetitive tasks. Macros can be used to emulate a sequence of keys pressed on the keyboard or can be programmed so that they can carry out more complicated processes.

3. Graphics packages Graphics packages have been divided into three basic categories: drawing (or painting) packages design packages presentation software. Other categories of graphics software include diagramming packages photo-editing programs.

4. Spreadsheets Spreadsheet packages are office software for processing numerical information. Spreadsheet packages are used for a variety of different purposes. Financial applications Common applications include production of cashflow forecasts, accounting statements, invoices, purchase orders, etc.

Spreadsheets Modelling and simulation Modelling involves creating a numerical representation of an existing situation or set of circumstances. Simulation involves predicting new situations or circumstances. In both cases, a model is produced that provides a numerical representation of the situation or circumstances being studied. An example is a cashflow forecast which is a numerical model that attempts to predict the financial state of a business over a given period of time. Once a model has been constructed, it can be manipulated so that users can see how changes to parts of the model influence the whole. A user might change the level of sales in a cashflow forecast to see how overall profit and loss would be affected. This ability to manipulate models is often referred to as what if analysis.

Spreadsheets Statistical analysis All spreadsheet programs provide a wide range of tools that can be used to analyze numerical information in a number of ways. Goal seeking describes a way of automatically changing the values in a formula until a desired result is achieved. Many programs offer a descriptive statistics feature which can be used to generate various summaries relating to a block of data.

Spreadsheet features A spreadsheet is a program designed to store and manipulate values, numbers and text in an efficient and useful way. Worksheets and cells. The work area in a spreadsheet program is called the worksheet. Formulae Functions Automatic features Formatting Charts Data analysis tools Import and export Workbooks

Figure 4.4 Organisation of a spreadsheet worksheet showing example formula

Databases Previously, almost all of the information an organization needed to store was organized using manual filing systems. A database is a collection of related information stored in an organized way so that specific items can be selected and retrieved quickly. A database need not involve the use of technology – examples of manual databases include telephone directories, address books, diaries and card index files.

Databases : key terms : entry Field: e.g. PO number, Date Each PO is a RECORD Collection of all POs is a Table PO Table Supplier Table Customer Table Order Table In this example each drawer is a table!

Business-level advantages of databases Databases are designed for sharing information. Multi-user access – allowing different people in the business access to the same data simultaneously such as a manager and another member of staff accessing a single customer’s data. Distributed access – users in different departments of the business can readily access data Speed – for accessing large volumes of information, such as the customers of a bank, only databases are designed to produce report or access the information rapidly about a single customer. Data quality – sophisticated validation checks can be performed when data are entered to ensure their integrity.

Business-level advantages of databases (Continued) Security – access to different types of data can readily be limited to different members of staff. Space efficiency – by splitting up a database into different tables when it is designed, less space is needed. (This process is called normalization .)

Databases (Continued) The information held in an electronic database is accessed via a Database Management System (DBMS). A DBMS can be defined as one or more computer programs that allow users to enter, store, organize, manipulate and retrieve data in a database. The data in an electronic database are organized by fields and records. A field is a single item of information such as a name or a quantity. A record is a collection of related fields and a table is a collection of related records.

Types of DBMS Relational databases enable data to be stored within a number of different tables. They are the most widely used type of database. The tables within a relational database can be linked together using one or more record keys. All database records must contain a unique record key (e.g. HKID card number) that can be used to identify a specific record. In a relational database, this is often called the primary key.

Types of DBMS Records can also contain other keys to help locate data stored in another table. The record keys contained in each table can be used to establish one or more relationships between tables. By using record keys in combination, it is possible to retrieve data from several tables at once. Note that a field used to locate information in another, related table is often called a foreign key .

Relational databases Figure 4.6 illustrates how records can be linked together using record keys. The diagram illustrates a simple relational database containing three tables: Customer, Order and Product.

Figure 4.6 An example of how key fields are used to link information from different database tables

Features of RDBMS All database programs enable users to create and edit tables or record structures. All packages allow users to enter, modify, delete, sort and extract records. The majority of packages also enable users to print data in a variety of different formats. Microsoft ACCESS is the best-known database used on the PC. Others include Borland Paradox, Lotus Approach and Microsoft Foxpro . These databases are mainly for personal or departmental use by a small number of users. Where databases are used by a large number of users, they are hosted on a mainframe or on a UNIX or Microsoft Windows NT server. These databases for “mission-critical” applications include ORACLE, Informix, Sybase, Microsoft SQL Sever and IBM DB2 .

Features of RDBMS (Continued) All major DBMS enable users to create and modify data entry forms which provide a convenient means of viewing, entering, editing and deleting records. An index stores information concerning the order of the records in the database. The index lists the locations of records but does not alter the actual order in the database. The index of a book can be used as a simple analogy. The index allows users to find a specific piece of information quickly and easily, regardless of how the material in the book is organized. Indexes are commonly used to increase the speed with which records can be located or sorted. Multiple indexes can be created so that the records in the database can be sorted in a variety of ways.

Databases : key terms : entry Name: Chaffey Address: 32 Cricket Street Oxford Postcode: OX5 6DG Tel: 01865 234 678 Manual record card system Field names Records Together equivalent to database table Screen form for Record entry Name Address1 Address2 Postcode Tel

Features of RDBMS (Continued) All major database packages allow users to generate a wide variety of reports . Many programs are capable of creating simple reports automatically. In addition, many programs allow users to perform calculations and other actions as the report is produced. This enables additional information, such as subtotals, to be calculated and included in the report whenever required. A query enables a user to locate, sort, update or extract records from the database. Users design a query by specifying the conditions that must be met in order for a record to be selected. The creation of a query is usually an interactive process.

Features of RDBMS (Continued) The majority of database programs make use of a special Structured Query Language (SQL) in order to create queries .

Structured Query Language (SQL) SQL provides a standardized method for retrieving information from databases. Traditionally, it is used to managed large databases held on mainframes and minicomputers. SQL is popular because it supports multi-user databases that operate across network systems. SQL programs are created by producing a series of statements containing special key words. The example shows a simple SQL query designed to search the Student Record table and display records for students with a Last Name of ‘Jones’. SELECT DISTINCTROW [Student Record].[Last Name] FROM [Student Record] WHERE ((([Student Record].[Last Name])=‘Jones’));

Structured Query Language (SQL) Users are often unaware that queries created using the interactive design tools provided by many modern database packages are converted into SQL programs before being executed. In Microsoft ACCESS, for example, a mouse is used to design a query on the screen. However, the query is translated into equivalent SQL statements before it is executed.

Productivity software Productivity software is general-purpose applications , aimed at supporting users in performing a variety of common tasks. This type of software can be sub-divided into a number of other categories. Personal information manager (PIM) Contact manager Presentation packages

Productivity software (Continued) Personal information manager (PIM) is a program that allows users to store, organize and retrieve personal information. A PIM can be thought as an electronic personal organizer. The program allows uses to store, organize and retrieve personal information such as appointments, personal expenses, telephone numbers and addresses, reminders and to-do lists. A PIM is usually made of several individual applications that are linked together by a menu system.

Productivity software (Continued) Contact manager is a software application that can be used to maintain lists of information relating to customers, suppliers and other important individuals or organizations. Network software describes the software used to establish workgroups on an organization’s network system. The programs used provide the basic infrastructure for workgroup computing. Scheduling software describes programs that help to organize the activities of the workgroup. Typical applications include calendars, scheduling programs and workflow software. *** A workgroup is defined as a group of individuals working together on a given task.

Productivity software (Continued) Presentation packages enables users to create, edit and deliver presentations via a computer system.

TOPICS 1. Categories of computer software 2. Document production software 3. Graphics packages 4. Spreadsheets 5. Databases 6. Management applications of productivity software 7. Multimedia software 8. Software for using the Internet

Multimedia software Multimedia is used to describe software which (together with appropriate hardware) can interact with the user through different techniques such as text, sound, animation or video. The type of hardware required to support multimedia includes sound and video cards and capture using microphones and video cameras.

Electronic mail Electronic mail (or email) is well known as a method of sending and receiving electronic messages. It has been available across the Internet for over 20 years. E-mails are typically written and read in a special mail reader program that in a large company is often part of a groupware package such as Lotus Notes, Microsoft Exchange or Novell Groupwise . Smaller companies or individuals may use lower-cost or free mail programs such as Microsoft Outlook Express, Eudora or Pegasus mail. A relatively recent innovation is the use of websites which provide free e-mail facilities and do not require any special software other than a web browser.

Advantages of e-mail Some of the major advantages of e-mail are: Speed -- E-mail messages can be transmitted very quickly. Cost – The cost of sending or receiving messages is considered very low. Multiple copies – E-mail allows multiple copies of the same basic message to be created and transmitted. Auditing – Even the simplest e-mail package will provide a number of features that allow users to audit their messages. Most programs allow users to keep copies of any messages they produce, automatically marking them with the date and time they were created.

Advantages of e-mail (Continued) Sharing data – E-mail messages can be used to transmit data file to other users. Files can be attached to messages and transmitted in the usual way. Multimedia – The latest e-mail packages allow users to include multimedia elements in their messages. Messages can include a variety of different elements including graphics, video, hyperlinks to information on the Internet, and sound files. Groupwork – E-mail supports groupwork and remote working.

Disadvantages of e-mail Routing – E-mail messages seldom take the most direct route to their destinations. This can lead to a number of difficulties: The time taken to receive the message can be long. There are more opportunities for the message to become lost. There are more opportunities for messages to be intercepted. Cost – Organizations must have access to the correct hardware and software. Technical issues – Novice users may find it difficult to operate the hardware and software involved. Spam – Unwanted messages, such as advertisements, are received by most email users. The act of sending out these messages is usually called spamming . Security – Unless encrypted, email messages can be intercepted relatively easily,

Features of an e-mail package Attachments Composition tools Viewing tools Filters Management tools Encryption Managing addresses – use of address book Signature files – a signature file contains information that can be automatically added to the end of an e-mail message.

World Wide Web and web browsers The World Wide Web (WWW) is a medium for publishing information on the Internet in an easy-to-use form. The medium is based on a standard document format known as HTML (hypertext mark up language) which can be thought of as similar to a word-processing format. It is significant since it offers hyperlinks which allow users to readily move from one document to another – the process known as “surfing”. The World Wide Web is accessed using a web browser . WWW pages feature sections of text that include hypertext links and graphics.

Features of a web browser The interface used by a web browser makes use of hypertext linking techniques. A hypertext is a document that includes highlighted words or phrases. These highlighted sections represent links to other documents or sections of the same document.

HTML HTML is the method used to create web pages and documents. The HTML code used to construct pages has codes or tags such as <TITLE> to indicate to the browser what is displayed. <HTML> tag Denotes an HTML document. <HEAD> tag The header part of an HTML document containing titles, meta tags and scripts. <TITLE> tag The text that appears in the browser title bar. <BODY> tag The main part of an HTML document containing content <! - -> tag Used to document code, text does not appear in browser

HTML example <HTML> <HEAD> <TITLE> The B2C Company</TITLE> </HEAD> <BODY> <!- main content starts here-> Welcome to the web site of the <B> B2C Company </B> </BODY> </HTML>

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