DEFINITION AND MEANING OF ECONOMICS Economics as a dynamic subject has very many definitions. It is often said that there are so many definitions of economics as there are economists because they see the subject from different point of view. Some definition given by some economists includes: Adam Smith (18th Century British Economist and Called […]
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Data are raw, unorganized or unprocessed facts that need to be processed. Data can be something simple and seemingly random and useless until it is organised. TYPES OF DATA Qualitative data i.e descriptive information Quantitative data i.e numeric information SUBDIVISION OF QUANTITATIVE DATA Continuous data: this can take any value. It is also known
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ICT has turned this world to a global village. Apart from communication, that is, reaching people both far and near; it has also made the work easier and better. Better productivity, salaries, health care and even farming and education. SECTORS WHERE ICT HAS PLAYED MAJOR ROLE Education Banking Industry Commerce EDUCATION ICT is applied in
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COMPONENTS OF A COMPUTER SYSTEM A computer system consists of three main parts otherwise called components. They are : Hardware Software People ware HARDWARE COMPONENT The computer hardware could be defined as the physical parts of the computer that we see, feel and handle. It consists of device for input, processing, storage, output and
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Digitalization is the process of converting information into digital format. This information may represent an object, image, sound, document or a signal (usually an analog signal) organized into discrete set of its points or samples. This is the binary data that computers and many devices with computing capacity (such as digital camera and digital hearing
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SUPER COMPUTER These are the largest, fastest and most expensive computers. The cost is several millions of dollars and the speed is between 600 million to 900 million instructions per second (MIP). Another name for super computer is MONSTER. Scientists in weather forecasting, exploration make use of super computers. It can also be used for
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Consider the table below: Generations Of computers Year of development The Technology Used Characteristics Software Instruction Storage Capacity First 1951-1958 Vacuum tube Very big and slow in operation Machine language Small internal storage Second 1959-1964 Transistor Less heat generation High level & Assembly Core storage Third 1965-1975 100-1000 Chips Introduction of integrated circuit
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FIRST GENERATION OF COMPUTERS Electronic machine which was distinct from mechanical computers evolved about 1945. UNIVAC is a good example of this generation of computers. Computers of this generation were characterized by: They used Vacuum tubes. They were very large and expensive. They were very bulky. They had a low retentive memory. They generated a
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EARLY MECHANICAL COUNTING/CALCULATING DEVICES Abacus Slide rule EARLY ELECTRO-MECHANICAL COUNTING DEVICES John Napier bone Blaize Pascal machine Gottfried Leitbnitz machine Joseph Jacquard Loom Charles Babbage analytical machine EARLY ELECTRONIC COUNTING DEVICES Herman Hollerith punch card John Von Neumann machine Man has put in every effort to have better methods of calculations. As
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In this chapter, you shall learn about what is data and information; the difference between data and information. Attempt to distinguish between manual and electronic data processing. DEFINITION OF DATA The term data means any basic fact which may be input to some processing system. A processing system is one where computations, comparisons and
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Crash recovery is the process by which the database is moved back to a consistent and usable state. This is done by rolling back incomplete transactions and completing committed transactions that were still in memory when the crash occurred. When the database is in a consistent and usable state, it has attained what is known
DEFINITION OF DATA SECURITY Data security is the practice of keeping data protected from corruption and unauthorized access. The focus behind data security is to ensure privacy while protecting personal or corporate data. It is a means of putting in place the different form of information security controls to protect database against compromise of
Maintenance is highly essential in order to prolong its contributing functionality. SOFTWARE MAINTENANCE The maintenance of programs inside the computer system such as virus, a spyware removal, back up software and a registry removal, cleaner. Every PC should be installed with an anti virus, a spyware removal application back up and a registry cleanser. Some
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Maintenance of computer hardware is a way of taking care, repairing and replacing broken and failing computer hardware. Maintenance is necessary on computer to avoid hardware failure or loosing valuable information and most times, hardware breaks without notice. Excess heat accelerates the deterioration of the delicate circuits in the system. Dust and dirt are the
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DENSE INDEX This is said to be dense if it contains (at least) one data entry for every search key value that appears in a record in the indexed file. In a dense index, index record appears for every search key value in the file or table. That is every search key in the index
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An Index is a copy of database table that has been reduced to certain fields and the copy is always in sorted form. The index also contains a pointer to the corresponding record of the actual table so that the fields not contained in the index can also be read. Index contains a value and