Research areas in Computer Science

A control unit is one of the two components of the central processing unit. The function of the control unit is to extract information which is stored in the memory and to decode and execute those instructions.

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It also takes help from the arithmetic logic unit , whenever required. The control unit is very important for computers functioning . The control unit has outputs which take charge of the activities of the entire device. Some regard the control unit to be an FSM or finite state machine which is used for hardware and software applications.
Control Unit and Microprogram :
There was a time when the manufacturing of control units was a difficult process, especially in designing it. But today the scenario has changed. A control unit is executed in the form of microprograms which remain in control stores. There is a micro sequencer which chooses the words and certain portions of those words which directly manage the various computer parts. These parts are arithmetic and logic units, buses, instruction registers, registers and input/output. Today the latest computers may possess subsidiary controllers for every subsystem, which would be supervised by the main control unit .
Functions of Control Unit:
A control unit can be described as a sort of circuitry that supervises and controls the path of information that runs over the processor and organizes the various activities of those units that lie inside it.
• It carries out many tasks such as decoding, fetching, handling the execution and finally storing the results.
• It controls the execution of instructions in a sequential order.
• It guides the flow of data through the different parts of the computer.
• It interprets the instructions.
• It regulates the time controls of the processor.

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• It sends and receives control signals from various peripheral devices. A control unit is a major computer part which helps in the functioning of the central processing unit and in turn runs the whole computer.

The invention of the computer

There is not just one inventor of the computer, as the ideas of many scientists and engineers led to its invention. These ideas were developed in the 1930s and 1940s, mostly independently of each other, in Germany, Great Britain and the USA, and were turned into working machines.

In Germany, Konrad Zuse hit upon the idea of building a program-controlled calculating machine when he had to deal with extensive calculations in statics. In 1935, he began to design a program-controlled calculating machine in his parents' home in Berlin. It was based on the binary system and used punched tape for the program input. The Z1, which was built between 1936 and 1938, was a purely mechanical machine which was not fully operational. In 1940, Zuse began to build a successor to the Z1 based on relay technology. In May 1941, he finished the Z3 - worldwide the first freely programmable program-controlled automatic calculator that was operational.
Several similar developments were in progress in the USA at the same time. In 1939, IBM started to build a program-controlled relay calculator on the basis of a concept that Howard H. Aiken had put forward in 1937. This machine - the IBM Automatic Sequence Controlled Calculator (Mark I) - was used on production work from 1944.

However, it was not Aiken's and Stibitz's relay calculators that were decisive for the development of the universal computer but the ENIAC, which was developed at the Moore School of Electrical Engineering at the University of Pennsylvania. Extensive ballistic computations were carried out there for the U.S. Army during World War II with the aid of a copy of the analog Differential Analyzer, which had been designed by Vannevar Bush, and more than a hundred women working on mechanical desk calculators. Nevertheless, capacity was barely sufficient to compute the artillery firing tables that were needed. In August 1942, John W. Mauchly, a physicist, presented a memo at the Moore School for a vacuumtube computer that was conceived as a digital version of the Differential Analyzer.

Mauchly had adopted John Vincent Atanasoff's idea for an electronic computer. Atanasoff had developed the ABC special-purpose computer at the Iowa State College (now Iowa State University) to solve systems of linear equations. Mauchly had viewed the ABC in June 1940. John Presper Eckert, a young electronic engineer at the Moore School, was responsible for the brilliant engineering of the new ENIAC. The work began on 31 May 1943 with funding from the U.S. Army. In February 1946, successful program runs were demonstrated.

At almost the same time, the Model I to Model VI relay calculators were built at Bell Laboratories in New York following a suggestion by George R. Stibitz.
John von Neumann, an influential mathematician, turned his attention to the ENIAC in the summer of 1944. While this computer was being built, von Neumann and the ENIAC team drew up a plan for a successor to the ENIAC. The biggest problem with the ENIAC was that its memory was too small. Eckert suggested a mercury delay-line memory which would increase memory capacity by a factor of 100 compared with the electronic memory used in the ENIAC.

An equally big problem was programming the ENIAC, which could take hours or even days.
In meetings with von Neumann, the idea of a stored-program, universal machine evolved. Memory was to be used to store the program in addition to data. This would enable the machine to execute conditional branches and change the flow of the program. The concept of a computer in the modern sense of the word was born.

In spring 1944, von Neumann wrote his "First Draft of a Report on the EDVAC" (Electronic Discrete Variable Computer) which described the stored-program, universal computer. The logical structure that was presented in this draft report is now referred to as the von Neumann architecture. This EDVAC report was originally intended for internal use only but it became the "bible" for computer pioneers throughout the world in the 1940s and 1950s.

The first two computers featuring the von Neumann architecture were not built in America but in Great Britain. On 21 June 1948, Frederic C. Williams of the University of Manchester managed to run the prototype of the Manchester Mark I, and thus proved it was possible to build a stored-program, universal computer. The first really functional von Neumann computer was built by Maurice Wilkes at Cambridge University. This machine called EDSAC first ran a program on 6 May 1949 computing a table of square numbers.

The advantage of learning about computers.

The advantage of being a computer literate is almost as clear as saying 'good day'. In today's world where everything has a computer element embedded in the system, having the basic knowledge about this wonder machine is like having a magic key which can open any door for you. Let us see what advantages a computer literate has over one who does not know anything about computers:
The CV is complete: The CV of one who has on it 'computer training' listed is indeed complete. There is no organization today worth its salt that does not use computers in some or other field in their systems. A person who seeks a job and has some basic training in computers says that the person is upto date with the existing technology and one who can do justice in a modern environment. Thus, one who has the computer training will always be chosen for the job interview/job vacancy over the one who does not - sometimes even if the latter is more qualified.
Intelligent and informed decision making power: Using the computer, one can analyze data and take informed decision about the future course of action. Those who do not understand computers and cannot use them, will not be able to profit of the in-depth analysis that a computer can put on your desk in matter of seconds after pressing a button. Not only that, you will be able to play around with the data and see what and where are the worst dangers of failure so you can plug these up with appropriate measures.
Business plan forecast: The computers are the best tools for predicting to a large extent what type of results a business plan would throw up. The banks base their sanctioning decision on the soundest possible plan and its financial forecast. Without computers one would have to work very hard to project the real balance sheet manually. The business forecast depends upon many factors which can be simultaneously taken care of by a computer while calculating the profit - loss sheets. However, with the manual method this is a cumbersome process which allows a lot of scope for mistakes. Sometimes a good plan is the only difference between a loan sanction and rejection.
Stay in touch: Electronic mail has spread rapidly to cover the whole globe in less than a decade. Now, the Internet is courting the telephone and today you can speak across the globe at the minimum possible rates and also see one another though web cameras. What a few decades ago was reserved for the sci-fi section of the libraries is today the truth. It is wonderful to see how you can communicate instantly with anyone, anywhere, anytime. Those who do not know to use the Internet for emails are total losers in the fact that they stay isolated or dependent on the snail mail when a few keys on the computer would bring them instant connectivity to their near and ear ones.
Saving time: Knowing computers is actually synonymous with simplification of life mundane tasks. Whether it is recording your favorite TV show in time and for the right duration or it is drawing up an annual financial plan for your company for the annual general meeting, computer usage cuts the time required to less than one tenth than it would have taken to do the task manually; up and above it, manual operations almost always allow for human error.
High accuracy of results: Computers being machines, provide highly accurate answers and calculations. Hence, a projected plan, a financial estimate, a profit and loss balance sheet are dependable once they are computed. The accuracy with which it can project and analyze data helps the computer literate understand better the ground reality of any given scenario while the computer illiterate would need to base his decisions on how dependable are the calculations and data of the staff who presented it.
Elimination of repetitive tasks: There are many times when you have to send 500 letters to prospective clients. A computer literate would use a database and mail-merge to get the whole thing on the road in no time, despite the fact that each letter would have a personalized printout addressing each of the prospective customers by their first names. One who does not know computers would not only need a week to complete the task, it will also make the task of repetitively writing addresses again and again.
Higher productivity: A computer literate can use his/her time better ensuring that results roll out faster and better. He/she can analyze accurately the data for any discrepancy or fault and correct it in time. He/she can also project the demand, most likely growth curve and the best expansion plan possible. Each of the above translates into higher productivity and benefit to the organization.
Self-learner culture: A computer literate will be constantly in need to upgrade his/he computer skills. He/she will also develop a self-learning attitude which is extremely conducive in any type of jobs. Employers are aware that those who have learned the use of computers are most of the times enthusiastic self-learners.
Problem self-diagnosis: Whether you are an engineer, a doctor or a common office manager, all must have at one time or other encountered different types of problems in the course of your job. When faced with a problem, most organization used to convene a meeting and brainstorm to seek a solution. A computer literate would use the computer to check out where the problem is. Once the problem is identified, the computer will again be used to help eliminate the problem.
A computer literate has tremendous advantage above those who are not. This is why most high schools and even degree colleges insist today on their students to complete the computer courses offered whether they feel they need it or not. You cannot really survive in today's technological jungle without knowing how to handle a computer.

The advantages of using a computerized accounting package such as MYOB accounting software.

The advantages of using a computerized accounting package such as MYOB accounting software.

Let me start this article by saying I am a qualified accountant who has taught accounting at a variety of levels for over 18 years. I have also worked extensively as a business consultant for small and medium size enterprises. I am continually amazed when I come across a business either not using a computerized accounting package or using spread sheets to do their accounts. Therefore I decided to write a short article on the benefits of using a computerized accounting package. The package I recommend for small to medium business is MYOB (Mind Your Own Business) accounting software package.

Small and medium sized businesses can now buy ‘off the shelf’ accounting programs at remarkably low cost. Larger businesses will often have customized programs made for their business. The accounting programs carry out functions such as invoicing, dealing with payments, paying wages and providing regular accounting reports such as trading and profit and loss accounts and balance sheets.

The introduction of computerized accounting systems provide major advantages such as speed and accuracy of operation, and, perhaps most importantly, the ability to see the real-time state of the company’s financial position. In my experience I have never seen a business that has upgraded to a computerized accounting system return to paper based accounting systems.
A typical computerized accounting package will offer a number of different facilities. These include:
On-screen input and printout of sales invoices
Automatic updating of customer accounts in the sales ledger
Recording of suppliers’ invoices
Automatic updating of suppliers' accounts in the purchases ledger
Recording of bank receipts
Making payments to suppliers and for expenses
Automatic updating of the general ledger
Automatic adjustment of stock records
Integration of a business database with the accounting program
Automatic calculation of payroll and associated entries
Computerized accounting programs can provide instant reports for management, for example:
Aged debtors’ summary – a summary of customer accounts showing overdue amounts
Trial balance, trading and profit and loss account and balance sheet
Stock valuation
Sales analysis
Budget analysis and variance analysis
GST/VAT returns
Payroll analysis
When using a computerized accounting system the on computer, input screens have been designed for ease of use. The main advantage is that each transaction needs only to be inputed once, unlike a manual double entry system where two or three entries are required.
The computerized ledger system is fully integrated. This means that when a business transaction is inputed on the computer it is recorded in a number of different accounting records at the same time.
The main advantages of a computerized accounting system are listed below:
Speed – data entry onto the computer with its formatted screens and built-in databases of customers and supplier details and stock records can be carried out far more quickly than any manual processing.
Automatic document production – fast and accurate invoices, credit notes, purchase orders, printing statements and payroll documents are all done automatically.
Accuracy – there is less room for errors as only one accounting entry is needed for each transaction rather than two (or three) for a manual system.
Up-to-date information – the accounting records are automatically updated and so account balances (e.g. customer accounts) will always be up-to-date.
Availability of information – the data is instantly available and can be made available to different users in different locations at the same time.
Management information – reports can be produced which will help management monitor and control the business, for example the aged debtors analysis will show which customer accounts are overdue, trial balance, trading and profit and loss account and balance sheet.
GST/VAT return – the automatic creation of figures for the regular GST/VAT returns.
Legibility ­– the onscreen and printed data should always be legible and so will avoid errors caused by poor figures.
Efficiency – better use is made of resources and time; cash flow should improve through better debt collection and inventory control.
Staff motivation – the system will require staff to be trained to use new skills, which can make them feel more motivated. Further to this with many ‘off-the-shelf’ packages like MYOB the training can be outsourced and thus making a particular staff member less critical of business operations.
Cost savings – computerized accounting programs reduce staff time doing accounts and reduce audit expenses as records are neat, up-to-date and accurate.
Reduce frustration – management can be on top of their accounts and thus reduce stress levels associated with what is not known.
The ability to deal in multiple currencies easily – many computerized accounting packages now allow a business to trade in multiple currencies with ease. Problems associated with exchange rate changes are minimized.

History of Computer
The first computers were people! That is, electronic computers (and the earlier mechanical computers) were given this name because they performed the work that had previously been assigned to people. "Computer" was originally a job title: it was used to describe those human beings (predominantly women) whose job it was to perform the repetitive calculations required to compute such things as navigational tables, tide charts, and planetary positions for astronomical almanacs. Imagine you had a job where hour after hour, day after day, you were to do nothing but compute multiplications. Boredom would quickly set in, leading to carelessness, leading to mistakes. And even on your best days you wouldn't be producing answers very fast. Therefore, inventors have been searching for hundreds of years for a way to mechanize (that is, find a mechanism that can perform) this task.

21st Century Technology

Now being in 21st century, thinking our life without computer is meaningless. It is such a useful machine which makes our work faster, easier & more reliable. Though it works on electricity, nowadays there are many more devices available which does not allow us to wait for electricity. It accuracy is 100%. Now adays it is used in variety of sectors. In each and every sector it is playing vital role. It may be school, govt. office, institutions, scientific technology and many inventions are possible through the help of computer. It is the hand of 21st century.