INTRODUCTION Information systems of different size and complexity can be found in a great variety of sectors
Information systems of different size and complexity can be found in a great variety
of sectors: government, education, healthcare, military organizations, media and entertainment and most parts of manufacturing industry, distribution, retailing and services, and so on. One of the contexts in which information systems are most important (and have been studied most significantly) is in business organizations. The use of Information Systems (IS) is very important for organizations, and each of them needs an Information System in this era to keep track of all business activities, starting from planning to the product delivery via manufacturing and quality cycles. IS is an essential tool that helps to achieve high level of efficiency and productivity in many types of business operations. But first, let us define what IS are. Information Systems are formal, sociotechnical, organizational systems, that consists of interrelated components, such as hardware, software, data, people, policies, procedures and sometimes feedback, that are designed to collect, process, store, transform and distribute information in order to support the day-to-day, short-range, and long-range activities of users in an organization. Note that data is acting as a bridge between hardware and people, and as soon as we involve people, data becomes an information, having a real value and meaning for the business.
Information systems generally are classified into several categories, where certain categories support parts of organizations, while others support entire organization, and still others, support groups of organizations. These categories are:
1) Transaction processing systems (TPS)
2) Management Information Systems (MIS)
3) Decision-support systems (DSS)
4) Executive Information system (EIS)
5) Office Information System (OIS)
6) Knowledge Work System (KWS)
To fulfil Information Systems’ feasible roles sufficiently, it has to be networked and secure, and have a good speed and storage capacity. In addition to being interconnected, “networked” means that employees can access the applications and systems they need from their work stations. Besides that, Information Systems must be secure, which means that only authorised personnel have access to given data and functions. Moreover, the system keeps the track of all the activities made in or with it. For the speed and capacity requirements it is important for businesses to have components that are powerful enough for operations and storage is large enough for storing all the data with ability to back it up.
In order to understand the information required by the users, we need to understand the various levels of an organization. To classify Information systems into different types we ned to see how task and responsibilities are divided within an organization. As most organizations are hierarchical, the way in which the different classes of information systems are categorized follow the same hierarchy.
For example, this is a three level pyramid model based on the type of decisions taken at different levels in the organization.
Operational management level
The operational level is concerned with performing day-to-day business transactions of the organization. Users at this level of management include cashiers at a point of sale, bank tellers, nurses in a hospital, customer care staff, etc.
Tactical Management Level
This organization level is dominated by middle-level managers, heads of departments, supervisors, etc. The users at this level usually oversee the activities of the users at the operational management level.
Strategic Management Level
This is the most senior level in an organization. The users at this level make unstructured decisions. Senior level managers are concerned with the long-term planning of the organization. They use information from tactical managers and external data to guide them when making unstructured decisions.
When we change our criteria to the different types of data and information that is processed in different levels, we can create a following model.
Basing the classification on the people who use the information system means that many of the other characteristics such as the nature of the task and informational requirements, are taken into account more or less automatically.
TYPES OF INFORMATION SYSTEMS
IS are classified into the categories depending on what their objectives are, who makes uses of information and to whom this information is reported. The following sections present each of these systems:
Transaction processing systems (TPS)
This system is used for daily routine transactions and serves the operational level of the organization. It is a computerized system that performs and records day-to-day and hour-to-hour transactions necessary for the running of the business. Those transactions include such business activities as a deposits, credit and debit cards, payments, orders or reservation, monthly payroll, etc.
Activities associated with transaction processing are usually performed by clerical staff and include the following:
1. Recording a business activity such as student’s registration, a customer’s order, an employee’s timecard pr a client’s payment.
2. Confirming an action or triggering a response, such as printing a student’s schedule, sending a thank-you note to a customer, generating an employee’s paycheque or issuing a receipt to a client.
3. Maintaining data, which involves adding new data, changing existing data, or removing unwanted data.
Most organisations started using computers primarily for these transaction processing purposes, because if these systems fail the company will be literally unable to operate. Transaction processing systems are often developed with a strong emphasis on saving time and money, that is efficiency and time saving, and it is often exhibit strong economies of scale. You should note, however, that efficiency is not the only criterion against which a transaction processing system should be judged. There is no point in being efficient at doing the wrong things. Therefore, we also have to think about effectiveness, as well as reliability of the undertaken process.
The first transaction processing systems used batch processing, which means that transaction data is collected over a period of time and all transactions are processed later, as a group. As computers became more powerful, system developers built online transaction processing systems. The computer processes transactions with online transaction processing (OLTP) as they are entered. When a student register for classes, his or her school probably uses OLTP. The registration administrative assistant enters the desired schedule and the computer immediately prints the statement of classes. The invoices, however, often are printed using batch processing, meaning all student invoices are printed and mailed at a later date.
Today, online transaction processing is still sometimes used along with batch processing because some tasks such as calculating paychecks or printing invoices are performed effectively on a batch basis.