information system (wikipedia)

http://en.wikipedia.org/wiki/Information_system

The term "information system" has different meanings:

• In computer security, an information system is described by the following components (Aceituno, 2004):
  • Structure:
    • Repositories, which hold data permanently or temporarily, such as buffers, RAM, hard disks, cache, etc. Usually, a database management system
    • Interfaces, which exchange information with the non-digital world, such as keyboards, speakers, scanners, printers, etc.
  • Channels, which connect repositories, such as buses, cables, wireless links, etc. A Network is a set of logical or physical: an introduction to informatics in Organisations. ^[1].
• The common view of an information system is that of an Information processor, that involves Input-Process-Output.

Information technology is a very important malleable resource available to executives.^[2] Many companies have created a position of Chief Information Officer (CIO) that sits on the executive board with the Chief Executive Officer (CEO), Chief Financial Officer (CFO), Chief Operating Officer (COO) and Chief Technical Officer (CTO).The CTO may also serve as CIO, and vice versa. The Chief Information Security Officer (CISO), who focuses on information security within an organization, normally reports to the CIO.

There are five types of information system. These are transaction processing systems, excutive support systems, business systems, knowledge work systems and office information systems.

Information Systems has a number of different areas of work:

• Information Systems Strategy
• Information Systems Management
• Information Systems Development

There are a wide variety of career paths in the information systems discipline. "Workers with specialized technical knowledge and strong communications skills will have the best prospects. People with management skills and an understanding of business practices and principles will have excellent opportunities, as companies are increasingly looking to technology to drive their revenue." ^[3]

From prior studies and experiences with information systems there are at least four classes of information systems:

• Transaction processing systems
• Management information systems
• Decision support systems
• Expert systems
• Business intelligence

Information System development

The IT Department partly governs the information technology development, use, application and influence on a business or corporation. A computer based information system, following a definition of Langefors^[4], is:

• a technologically implemented medium for recording, storing, and disseminating linguistic expressions,
• as well as for drawing conclusions from such expressions.

which can be formulated as a generalized information systems design mathematical program.