Cookie

A cookie is information that a Web site puts on your hard disk so that it can remember something about you at a later time. (More technically, it is information for future use that is stored by the server on the client side of a client/server communication.)

Typically, a cookie records your preferences when using a particular site. Using the Web's Hypertext Transfer Protocol (HTTP), each request for a Web page is independent of all other requests. For this reason, the Web page server has no memory of what pages it has sent to a user previously or anything about your previous visits.

A cookie is a mechanism that allows the server to store its own information about a user on the user's own computer. You can view the cookies that have been stored on your hard disk (although the content stored in each cookie may not make much sense to you).

The location of the cookies depends on the browser. Internet Explorer stores each cookie as a separate file under a Windows subdirectory. Netscape stores all cookies in a single cookies.txt fle. Opera stores them in a single cookies.dat file.

BeOS

BeOS is a personal computer operating system that its makers describe as designed for the multimedia applications of the future. Be founder Jean-Louis Gasse left Apple Computer in 1990 to create an operating system that could exploit new architectural ideas and be free of the baggage that older operating systems invariably bring with them. The first BeOS was used in a computer called the BeBox, since abandoned so the company could concentrate on the software. In 1996, BeOS had Apple's Macintosh users in mind when it ported the system to the PowerPC microprocessor. More recently, BeOS has been ported to Intel's Pentium computers. It can be installed in the same computer with another operating system such as Windows or Mac OS and used as an alternative operating system for applications requiring fast handling of streaming video, games, and other multimedia applications.

Real-time Operating System

A real-time operating system (RTOS) is an operating system that guarantees a certain capability within a specified time constraint. For example, an operating system might be designed to ensure that a certain object was available for a robot on an assembly line. In what is usually called a ''hard'' real-time operating system, if the calculation could not be performed for making the object available at the designated time, the operating system would terminate with a failure. In a ''soft'' real-time operating system, the assembly line would continue to function but the production output might be lower as objects failed to appear at their designated time, causing the robot to be temporarily unproductive. Some real-time operating systems are created for a special application and others are more general-purpose. Some existing general purpose operating systems claim to be real-time operating systems. To some extent, almost any general-purpose operating system such as Microsoft's Windows 2000 or IBM's OS/390 can be evaluated for its real-time operating system qualities. That is, even if an operating system doesn't qualify, it may have characteristics that enable it to be considered as a solution to a particular real-time application problem.

Compiled by G. Rajah

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