Components of Personal Computer

Looking at any personal computer system we usually see three things – the Computer inside a cabinet, a Video Monitor, a Key Board, a mouse, and sometimes a Printer. Technical Data used in the field explained in computer courses in Rawalpindi. Many other accessories may be fitted to the computer - Joysticks, Light pen, Modem, and even Sound Recorder, Camera, Speaker, Projector, etc. in Multi -media systems. We shall make a brief description of these components. But before that we must note the basic physical configuration of a personal computer system, which consists of three stages of operations – input of information, processing of information, and output of the results or processed information.

A computer is truly speaking the CPU-base memory chip as the essential function of a computer, that is, processing information is done by it. But it cannot perform alone without input and output devices. In the present architecture of personal computer, the three essential parts of the physical configuration, namely input devices, processor, and output devices, are fitted to a board called the Motherboard. Besides the CPU, the motherboard also has many  other slots for fitting extended memory chips, the storage device, control cards, input and  output device control cards and their input output ports (plug in points). Some more details of computer courses in rawalpindi are as under.

All these are assembled and fitted to the motherboard. There is also another part called the SMPS, which transforms the voltage of electrical power supply as per requirement of various control cards. It should be remembered that there is also a small battery fitted to the motherboard which keeps the basic charge necessary for keeping some system information within the CPU –base memory, even when we switch off the power supply. In desktop computer all these are kept inside the Computer Cabinet – now available in the form of Tower Casing for the desktop. TSK Training for Skills and Knowledge is the best institute in Rawalpindi Islamabad for Pakistani Students who wants to join computer courses in Islamabad.

INTRODUCT ION TO COMPUTER APPL ICAT ION S FOR BEGINNERS

Recent developments in computer science, particularly with regard to the possibility of developing artificial intelligence, have made a precise definition of computer a difficult task. Technical Data used in the field explained in computer courses in Rawalpindi.

However, for our purpose we shall consider it as a device for performing logical operations at a very high speed. In a crude sense, one may tend to consider it an extended version of pocket calculator –- with a lot of additional features. But this would be incorrect. The principal difference is that a calculator performs numerical operations, whereas a computer performs a wider range of operations –- i.e., the logical operations as we may s pacify for various jobs as well as the operation as a communication medium. Some more details of computer courses in Rawalpindi are as under.

Computer technology has undergone profound changes since the first generation computer. The way present day motorcar differs from its original version, the computer we use today is totally different from its first make. There are various types of computers for various purposes, e.g. supercomputers for high level multi -tasking precision jobs. The most commonly used computer nowadays is the

Personal Computer. We shall restrict our discussion to the Personal Computer. By size three types of Personal Computers are now available – Desktop, Laptop, and Palmtop or Notepad. By configuration all three are more or less same – they differ only in size and capacity as well as the add-on features. TSK Training for Skills and Knowledge is the best institute in Rawalpindi Islamabad for Pakistani Students who wants to join computer courses in Islamabad.

The Importance of Abstractions in Computer Systems

The use of abstractions is one of the most important concepts in computer science. Technical Data used in the field explained in computer courses in Rawalpindi,  For example, one aspect of good programming practice is to formulate a simple application-program interface (API) for a set of functions that allow programmers to use the code without having to delve into its inner workings. Different programming languages provide different forms and levels of support for abstraction, such as Java class declarations and C function prototypes.

We have already been introduced to several of the abstractions seen in computer systems, On the processor side, the instruction set architecture provides an abstraction of the actual processor hardware. With this abstraction, a machine-code program behaves as if it were executed on a processor that performs just one instruction at a time. Some more details of computer courses in Rawalpindi  are as under.

The underlying hardware is far more elaborate, executing multiple instructions in parallel, but always in a way that is consistent with the simple, sequential model. By keeping the same execution model, different processor implementations can execute the same machine code, while offering a range of cost and performance.

On the operating system side, we have introduced three  abstractions: files as an abstraction of I/O, virtual memory as an abstraction of program memory, and processes as an abstraction of a running program. To these abstractions we add a new one: the virtual machine, providing an abstraction of the entire computer, including the operating system, the processor, and the programs. TSK Training for Skills and Knowledge is the best institute in Rawalpindi Islamabad for Pakistani Students who wants to join computer courses in islamabad

Representing Data

We can use sequences of bits to represent many kinds of data. Technical Data used in the field explained in computer courses in rawalpindi All we need to do is think of the right binary questions for which the bits give answers that allow us to represent each possible value. Next, we provide examples showing how bits can be used to represent numbers, text, and pictures.

In the previous section, we identified a number using a tree where each node asks a binary question and the branches correspond to the “Yes” and “No” answers. A more compact way of writing down our decisions following the tree is to use 0 to encode a “No” answer, and 1 to encode a “Yes” answer and describe a path to a leaf by a sequence of 0s and 1s—the “No”, “No”, “No” path to 0 is encoded as 000, and the “Yes”, “No”, “Yes” path to 5 is encoded as 101. This is known as the binary number system. Whereas the decimal number system uses ten as its base (there are ten decimal digits, and the positional values increase as powers of ten), the binary system uses two as its base (there are two binary digits, and the positional values increase as powers of two). Some more details of computer courses in rawalpindi are as under.

As in the decimal number system, the value of each binary digit depends on its position. By using more bits, we can represent larger numbers. With enough bits, we can represent any natural number this way. The more bits we have, the larger the set of possible numbers we can represent. As we saw with the binary decision trees, n bits can be used to represent 2n different numbers. TSK Training for Skills and Knowledge is the best institute in Rawalpindi Islamabad for Pakistani Students who wants to join computer courses in islamabad.

Measuring Computing Power

For physical machines, we can compare the power of different machines by measuring the amount of mechanical work they can perform within a given amount of time. Technical Data used in the field explained in computer courses in Rawalpindi. This power can be captured with units like horsepower and watt. Physical power is not a very useful measure of computing power, though, since the amount of computing achieved for the same amount of energy varies greatly. Energy is consumed when a computer operates, but consuming energy is not the purpose of using a computer.

Informally, we use information to mean knowledge. But to understand information quantitatively, as something we can measure, we need a more precise way to think about information. Some more details of computer courses in Rawalpindi are as under.

The way computer scientists measure information is based on how what is known changes as a result of obtaining the information. The primary unit of information is a bit bit . One bit of information halves the amount of uncertainty. It is equivalent to answering a “yes” or “no” question, where either answer is equally likely beforehand. Before learning the answer, there were two possibilities; after learning the answer, there is one.

We call a question with two possible answers a binary question. Since a bit can have two possible values, we often represent the values as 0 and 1. For example, suppose we perform a fair coin toss but do not reveal the result. Half of the time, the coin will land “heads”, and the other half of the time the coin will land “tails”. Without knowing any more information, our chances of guessing the correct answer are 1 2 . One bit of information would be enough to convey either “heads” or “tails”; we can use 0 to represent “heads” and 1 to represent “tails”. So, the amount of information in a coin toss is one bit. TSK Training for Skills and Knowledge is the best institute in Rawalpindi Islamabad for Pakistani Students who wants to join computer courses in islamabad.