Computer Terminology

• Advantages of Interactive Graphics

Graphics provides one of the most natural means of communicating with a computer, since our highly developed 2D and 3D pattern-recognition abilities allow us to perceive and process pictorial data rapidly and efficiently. In Many design, implementation, and construction processes today, the information pictures can give is virtually indispensable. Scientific visualization became an important field in the late 1980s, when scientists and engineers realized that they could not interpret the data and prodigious quantities of data produced in supercomputer runs without summarizing the data and highlighting trends and phenomena in various kinds of graphical representations.

Creating and reproducing pictures, however, presented technical problems that stood in the way of their widespread use. Thus, the ancient Chinese proverb "a picture is worth ten thousand words" became a cliché in our society only after the advent of inexpensive and simple technology for producing pictures---first the printing press, then photography.

Interactive computer graphics is the most important means of producing pictures since the invention of photography and television; it has the added advantage that, with the computer, we can make pictures not only of concrete, "real-world" objects but also of abstract, synthetic objects, such as mathematical surfaces in 4D and of data that have no inherent geometry, such as survey results. Furthermore, we are not confined to static images. Although static pictures are a good means of communicating information, dynamically varying pictures are frequently even better--to time-varying phenomena, both real (e.g., growth trends, such as nuclear energy use in the United States or population movement form cities to suburbs and back to the cities). Thus, a movie can show changes over time more graphically than can a sequence of slides. Thus, a sequence of frames displayed on a screen at more than 15 frames per second can convey smooth motion or changing form better than can a jerky sequence, with several seconds between individual frames. The use of dynamics is especially effective when the user can control the animation by adjusting the speed, the portion of the total scene in view, the amount of detail shown, the geometric relationship of the objects in the another, and so on. Much of interactive graphics technology therefore contains hardware and software for user-controlled motion dynamics and update dynamics.

With motion dynamics, objects can be moved and tumbled with respect to a stationary observer. The objects can also remain stationary and the viewer can move around them , pan to select the portion in view, and zoom in or out for more or less detail, as though looking through the viewfinder of a rapidly moving video camera. In many cases, both the objects and the camera are moving. A typical example is the flight simulator, which combines a mechanical platform supporting a mock cockpit with display screens for windows. Computers control platform motion, gauges, and the simulated world of both stationary and moving objects through which the pilot navigates. These multimillion-dollar systems train pilots by letting the pilots maneuver a simulated craft over a simulated 3D landscape and around simulated vehicles. Much simpler fight simulators are among the most popular games on personal computers and workstations. Amusement parks also offer "motion-simulator" rides through simulated terrestrial and extraterrestrial landscapes. Video arcades offer graphics-based dexterity games and racecar-driving simulators, video games exploiting interactive motion dynamics: The player can change speed and direction with the "gas pedal" and "steering wheel," as trees, buildings, and other cars go whizzing by. Similarly, motion dynamics lets the user fly around the through buildings, molecules, and 3D or 4D mathematical space. In another type of motion dynamics, the "camera" is held fixed, and the objects in the scene are moved relative to it. For example, a complex mechanical linkage, such as the linkage on a stream engine, can be animated by moving or rotating all the pieces appropriately.

Update dynamics is the actual change of the shape, color, or other properties of the objects being viewed. For instance, a system can display the deformations of an airplane structure in flight or the state changes in a block diagram of a nuclear reactor in response to the operator's manipulation of graphical representations of the many control mechanisms. The smoother the change, the more realistic and meaningful the result. Dynamic interactive graphics offers a large number of user-controllable modes with which to encode and communicate information: the 2D or 3D shape of objects in a picture, their gray scale or color, and the time variations of these properties. With the recent development of digital signal processing (DSP) and audio synthesis chips, audio feedback can now be provided to augment the graphical feedback and to make the simulated environment even more realistic.

Interactive computer graphics thus permits extensive, high-bandwidth user-computer interaction. This significantly enhances our ability to understand data, to perceive trends, and to visualize real or imaginary objects--indeed, to create "virtual worlds" that we can explore from arbitrary points of view. By making communication more efficient, graphics make possible higher-quality and more precise results or products, greater productivity, and lower analysis and design costs.

A Terabyte is 1 trillion (1,000,000,000,000) bytes of memory, that in most cases is related to computer technology. It is equal to 1,024 gigabytes.

- A terabyte (TB) is a measure of computer storage capacity that is 2 to the 40th power or approximately a trillion bytes (that is, a thousand gigabytes). The prefix tera is derived from the Greek word for monster.

Hitachi began selling 1-terabyte hard drives to consumers in 2007. (Today, consumers can purchase a 2-terabyte external hard drive for around $180.) A one terabyte drive can hold:

• 472 hours of broadcast quality video.
• 150 hours of hi-definition recording.
• Enough words that it would take every adult in America speaking at the same time five minutes to say them all.

According to futurist Raymond Kurzwell is "The Singularity is Near," the capacity of a human being's functional memory is estimated to be 1.25 terabytes.

-moi

1. Hertz (MHz, GHz)
2. hertz (Hz) as a unit is defined as the number of cycles per second, making 1 megahertz (MHz) one million cycles per second, while 1 gigahertz is 10^9 hertz. Vibrations and electromagnetic radiation are measured in hertz units, but in computing it is the clock speed of the central processing unit that is referenced in terms of hertz. CPU
3. In the broadest terminology, a CPU or processor is the element of a computer that carries out received programming. The CPU is usually an integrated circuit called a microprocessor which carries out the functions of retrieving, decoding, carrying out, and writing back (providing further instruction). This process is one cycle, measured in terms of the computer's clock speed. Clock speed
4. A crystal oscillator, a vibrating metal crystal which is another circuit in a computer, provides a signal (clock signal) which determines the computer's clock speed (or rate), that is, the speed at which a CPU completes one cycle. Thus, a CPU at 1 GHz is completing 1 billion cycles per second (carrying out 1 billion programming instructions). In computing, it is very important that this signal remain precisely constant. Comparisons
5. Because of variances in the ways in which different machines and processors execute operations, it is not always possible for the casual user to tell ahead of time which type of machine and processor will perform a task the most quickly. This means that using the clock speed (Hz measurement) of a system will not always indicate how quickly that system will perform a task in relationship to other systems.

Hope be helpful!

GB (gigabytes) is bigger than MB (megabytes).

• 1 kilobyte (KB) = 1024 bytes.
• 1 megabyte (MB) = 1024 kilobytes.
• 1 gigabyte (GB) = 1024 megabytes.
• 1 terabyte (TB) = 1024 gigabytes.