INF1505 SUMMARY notes latest

CHAPTER 1 An Introduction to Information Systems (IS) Information Systems are used in almost every imaginable profession, for example:  Sales representatives use information systems to advertise products, communicate with customers and analyse sales trends  Managers use them to make decisions, such as whether to build a manufacturing plant or research a cancer drug 1. What is an Information System? First we need to break it down to get to the understanding and definition of IS: 1.1 What is a System? It is a set of elements or components that interact to accomplish goals. A system consist of four component:  Input – the activity of gathering and capturing data  Processing – converting or transforming data into useful outputs  Output – production of useful information, often in the form of documents and reports  Feedback – output that is used to make changed to input or processing activities 1.2 What is Information? Simply a collection of facts. Characteristics of Valuable Information: Characteristics Definitions Accessible Easily accessible by authorized users Accurate Information that is error free Complete Contains all the important information Economical Cost versus benefit is worthy Flexible Information is useful in different areas Relevant Contains Information that is important to decision makers Reliable Contains information you can depend on Secure Safe from authorized users Simple Not complex or difficult to understand Timely Delivered when needed Verifiable Check to verify if correct Therefore, an Information system is a set of interrelated components that collect, manipulate, store and disseminate information and provide a feedback mechanism to meet an objective Manual and Computerised Information Systems  A Computer-based Information System (CBIS) is a single set of hardware, software, database, telecommunications, people, and procedures that is configured to collect, manipulate, store, and process data into information. Components of a CBIS Hardware – any machinery that assists in the input, processing, storage, and output activities of an information system (e.g. Keyboard, mouse, Monitor etc.) Software – the computer programs that govern the operation of the computer (e.g. Microsoft Windows) Database – an organised collection of electronic information Telecommunications – the electronic transmission of signals for communications; enables organisations to carry out their processes and tasks through effective computer networks. Usually involves the following: o Networks – computers and equipment that are connected in a building, around the country or around the world to enable electronic communication o Internet – the world’s largest computer network, actually consisting of thousands of interconnected networks, all freely exchanging information o Cloud Computing – a computing environment where software and storage are provided as an internet service and are accessed via a Web browser o Intranet – an internal company network built using internet and World Wide Web standards and products that allows people within an organisation to exchange information and work on projects o Extranet – a network based on web technologies that allows selected outsiders, such as suppliers or business partners to access authorised resources of a company’s intranet People – users of the system Procedures – the strategies, policies, methods and rules for using a CBIS 2. Business Information Systems 2.1 Transaction Processing Systems (TPS) A transaction is any business related exchange, such as payments to employees, sales to customers and payments to suppliers. Therefore, a TPS is an organised collection of people, procedures, software, databases and devices used to record completed business transactions. 2.2 Enterprise Resource Planning (ERP) A set of integrated programs capable of managing a company’s vital business operations for an entire multisite, global organisation. It checks what is already available in finished products inventory to meet the projected demand 2.3 Management Information Systems (MISs) Is an organised collection of people, procedures, software, databases, and devices that provides routine information to managers and decision-makers