A final example on how information systems benefit large firms by lower costs and allowing them to deliver products and services at lower cost is Wal-Mart. By keeping prices low and shelves well stocked, Wal-Mart uses an outstanding inventory replenishment system triggered by point-of-sale purchases. This is considered the best system in the industry. This continuous replenishment system sends orders to suppliers as soon as the customer at the register purchases the product. Point-of-sale terminals record the bar code of each item passing the checkout counter and send a purchase transaction directly to a central computer at Wal-Mart Headquarters. The computer collects orders from all of the Wal-Mart stores and transmits them to suppliers. Because this system allows them to replenish inventory very fast, Wal-Mart does not spend as much money on stock pilling inventory as its competitors. Wal-Mart only spends 15 percent of sales in overhead while Sears spends 30 percent and Kmart spends 21 percent.
Again, this is only possible because of the use of information systems. As you can see, information systems are far more than just input, process, and output machines. Managers and society must understand that these systems provide solutions to business challenges and must be willing to change with the new technology. Information systems can help in the day-to-day task at work and at home. We no longer have to depend on only one firm or corporation to buy material we need. We can shop the global market 24 hours a day to find the best price and quality. With the increased global competition, companies will have to use information systems in order to survive in todays market place. UNIX was slow to catch on outside of academic institutions but soon was popular with businesses as well.
Market information system may be defined as factual knowledge about the action, antecedents or consequences of social actors outside or inside the firm and the environment in which they operate. Social actors are as consumers, completions, employee, institutions, suppliers, wholesalers, retailers, govt. bodies and NGO’s. The environment actors are physical, technological, economic, legal and ...
The first five versions were part of an internal research effort of Bell Labs, and it was not until the sixth version, called UNIX Timesharing Sixth Edition V, that UNIX was widely distributed (Osiris, 1).
Relatively recent developments are graphical interfaces (GUI) such as MOTIF, X Windows and Open View. UNIX has two major versions. Jointly developed by UNIX Systems Laboratories (USL) and by AT&T researchers together with Bell Labs, generically known as System V, is the commercial version and is the most widely distributed by major manufacturers. The second, developed by the University of Berkley and Berkley Software Distribution (BSD), is the educational version and is completely focused on research. The USL version is now on its fourth release, or SVR4, while BSDs latest version is 4.4. However, there are many different versions of UNIX besides these two.
The operating system has been licensed to several manufacturers who in turn developed their own versions of UNIX, based on System V or BSD, but adding new characteristics. Most versions of UNIX developed by software companies are derived from one of the two groupings and, recent versions of UNIX actually incorporate features from both of them. However, UNIX has had an unregulated history with over 200 versions (Berson, 16) existing today. The UNIX system is made up of three primary components, the kernel, the shell, and the utilities (which includes the file system).
The central part of the OS, the kernel is the first program to start when the system is turned on and the last program to do anything when the system is halted. In addition to scheduling tasks, it manages data/file access and storage, enforces security mechanisms and performs all hardware access. The name KERNEL represents the fact that it is a program designed as a central nucleus, around which other functions of the system were added.
The heart of the operating system, it not only interacts directly with the systems hardware, but presents each user with a prompt, interprets commands typed by a user, executes user commands and supports a custom environment for each user. The two most common shells are the Bourne shell, default for the System V, and the C-shell used mainly with the BSD version (Osiris, 1).
Where Did UNIX Come From and Why Are There Different Versions Of UNIX? The first efforts at developing a multi-user, multi-tasking operating system were begun in the 1960's in a development project called MULTICS. While working for Bell Telephone Laboratories in 1969 and 1970, Ken Thompson and Dennis Ritchie began to develop their own single-user, multi-tasking small operating system and they ...