1. Mnam salem Faculty of computer and information s.c.u
INFORMATION SYSTEM
Mnam salem
Faculty of computer
and information
s.c.u

2. Components of information systems:
The main components of information systems are   and , telecommunications,  and data warehouses, human resources, and procedures. The hardware, software, and telecommunications constitute information  (IT), which is now ingrained in the operations and management of organizations.

3. Computer hardware:
Today even the smallest firms, as well as many households throughout the world, own or lease computers. These are usually , also called personal computers. Individuals may own multiple computers in the form of smartphones and other portable devices. Large organizations typically employ distributed computer systems, from powerful parallel-processing servers located in data centres to widely dispersed personal computers and mobile devices, integrated into the organizational information systems. Together with the peripheral equipment, such as magnetic or solid- state  disks, , and telecommunications gear, these constitute the hardware of information systems. The cost of hardware has steadily and rapidly decreased, while processing speed and storage capacity have increased vastly. However, hardware’s use of electric power and its environmental impact are concerns being addressed by designers.

5. Computer software:
Computer  falls into two broad classes:  and application software. The principal system software is the . It manages the hardware, data and program files, and other system resources and provides means for the user to control the computer, generally via a  (GUI).  is programs designed to handle specific tasks for users. Examples include general-purpose application suites with their spreadsheet and  programs, as well as “vertical” applications that serve a specific industry segment—for instance, an application that schedules, routes, and tracks package deliveries for an overnight carrier. Larger firms use licensed applications, customizing them to meet their specific needs, and develop other applications in-house or on an outsourced basis. Companies may also use applications delivered as software-as-a-service (SaaS) over the Web. Proprietary software, available from and supported by its vendors, is being challenged by software available on the Web for free use and modification under a license that protects its future availability.

6. Human resources and procedures:
Qualified people are a vital component of any information system. Technical personnel include development and operations managers, business analysts, systems analysts and designers, database administrators, computer programmers, computer security specialists, and computer operators. In addition, all workers in an organization must be trained to utilize the capabilities of information systems. Billions of people around the world are learning about information systems as they use the Web.

7. Types of information systems:
Information systems support operations, knowledge work, and management in organizations. (The overall structure of organizational information systems is shown in the .) Functional information systems that support a specific organizational function, such as marketing or production, have been supplanted by cross-functional systems. Such systems can be more effective in the development and delivery of the firm’s products and can be evaluated more closely with respect to the business outcomes.

8. Support of knowledge work:
abstract information and knowledge (understood in this context as an organized and comprehensive structure of facts, relationships, theories, and insights) rather than directly processing, manufacturing, or delivering tangible materials. Such work is called knowledge work. Three general categories of information systems support such knowledge work: professional support systems, collaboration systems, and knowledge management systems.

9. PROFESSIONAL SUPPORT SYSTEMS:
Professional support systems offer the facilities needed to perform tasks specific to a given profession. For example, automotive engineers use  (CAE) software together with  systems to design and test new models for fuel efficiency, handling, and passenger protection before producing prototypes, and later they use CAE in the design and analysis of physical tests. Biochemists use specialized three-dimensional modeling software to visualize the molecular structure and probable effect of new drugs before investing in lengthy clinical tests.  bankers often employ financial software to calculate the expected rewards and potential risks of various investment strategies. Indeed, specialized support systems are now available for most professions.

10. Information systems security:
Charles P. Pfleegerzand Shari Lawrence Pfleeger, Security in Computing, 4th ed. (2007), is a comprehensive survey of threats to information systems security and the measures to counteract them. Andy Jones andDebi Ashenden, Risk Management for Computer Security: Protecting Your Network and Information Assets(2005), is an integrated treatment of the organizational assessment of IT risks.

11. Information systems as a discipline:
Izak Benbasat and Ron Weber, “Rethinking ‘Diversity’ in Information Systems Research,” Information Systems Research, 7(4):389–399 (1996), provides a commentary on the interdisciplinary nature of the information systems discipline. John Mingers and Leslie Willcocks, Social Theory and Philosophy for Information Systems (2004), presents several theoretical foundations for the discipline of information systems. William H. Delone and Ephraim R. McLean, “The DeLone and McLean Model of Information Systems Success: A Ten-Year Update,” Journal of Management Information Systems 19(4):9–30 (Spring 2003), is an integrative framework of the metrics of information systems success.

12. Thank you !!