Sunday, 28 August 2016
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Information technology (IT) is the application of computers and internet to store, retrieve, transmit, and manipulatedata,[1] or an information often in the context of a business or other enterprise
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1. A computer system is defined as combination of components designed to process data and store files. A computer system consists of four major hardware components; input devices, output devices, processor and storage devices. A computer system requires hardware, software and a user to fully function.
2. • Input is any data or instructions that we enter into the computer system for processing. There are four types of input: which are text, graphic, audio and video. Example of input devices are keyboard, light pen, joystick, microphone, mouse, video & digital camera. input • The processing unit controls all activities within the system. The CPU is an example of a processor. It has the same important as the brain to human being.process • Storage is a location which data, instruction and information are held for future use. It is the physical material that keeps keeps data, instruction and information. There are two types of storage. They are the primary storage and secondary storage. The exampleStorage of storage devices are hardisk, Floppy Disk, diskette, RAM, CD ROM and DVD ROM. • Output is data that has been processed into a useful form, called information. There are four types of output, which are texts, graphics, audio and video. Example of output devices are monitor, printer, speaker and plotter.output
3. input process storage•Users input data or instruction •Data or instruction being input •Computer storage is important to into the computer system to be into the computer system is then help users store programs and data process. Input could be either processed by the CPU which to be used at a later time. text, graphic, audio or video. controls all activities within the •It is also useful to keep current Input devices are used by users to system. The results of the data while being processed by the input data. Input devices are any processed data are then sent to an processor until the information is electronic device connected to a output device as usable data. saved in a storage media such as a computer and produces input •A CPU interprets the and carries hard disk or a diskette. Computer signals. out the instructions by processing storage also stores instructions data and controlling the rest of from a computer program. There the computer’s components. are two type of computer storage; •A CPU consists of two primary storage and secondary subcomponents; the Control Unit storage. (CU) and the Arithmetic Logic Unit (ALU). CU’s main function is to direct the CPU to process data by extracting instructions from memory and decodes and executes them. The CU manages a four-step basic operation which is called a machine cycle. The steps are Fetching, Decoding, Executing & Storing
4. Binary digitCharacter Bit codes Character Byte
5. BINARY DIGIT Computers recognize only two discrete states: on and off. These states can be represented by two digits, 0 and 1. Each 0 or 1 is called a bit in the binary system. Bit is the smallest unit of data a computer can process. Bit is a short for binary digit. The binary system has a base of 2 with the two digits (0 and 1). Combinations of 0s and 1s represent larger numbers.BIT A bit is the smallest unit of data that the computer can process. Bit is a short for binary digit. A bit is represented by the numbers 1 and 0. These numbers represent the binary system. They correspond to the states of on and off, true and false, or yes and no. All digital data use the binary system to process the information. This information include letters, digits or special character.BYTE Byte is a unit of information built from bits. One byte is equals to 8 bits. Eight bits that are grouped together as a unit. A byte provides enough different combinations of 0s and 1s to represent 256 individual characters. One byte represents a single character such as the number 3, letter b or a $ symbol. Bits and bytes are the basis for representing all meaningful information and programs on computers.
6. CHARACTER 8 bits = 1 byte One byte represents one character such as A, 7, 9 and +.Eight bits that are grouped together as a unit. A byte provides enough different combinations of 0s and 1s to represent 256 individual characters. For example, the capital letter F is represented by the binary code 01000110 that can be understood by the computer system. Eight bits grouped together as a unit are called a byte. A byte represents a single character in the computer.CHARACTER CODES There are three character codes to represent characters which are ASCII, EBCDIC and Unicode. Each byte contains eight bits. A byte provides enough different combination of 0s and 1s to represent 256 characters. The combinations of 0s and 1s are defined by patterns. These patterns are called coding scheme. The 256-character capability of ASCII and EBCDIC is too small to handle the characters that are used by other languages such as Arabic, Japanese and Chinese. The Unicode coding scheme is designed to solve this problem. It uses two bytes (16 bits) to represent one character. Unicode will have more than 65,000 different characters. This can cover all the world’s languages.
7. ASCII code ASCII pronounced as "ask-key" stands for the American Standard Code for Information Interchange and was proposed by ASA (American Standard Association) in 963 and was finalised in 1968.ASCII is a standard of 7-bit code used to represent characters, which include letters, numbers and punctuation marks. 7 bits allow the computer to encode a total of 128 characters for the numbers 0-9, uppercase and lowercase letters A-Z and a few punctuation symbols. However this 128 bit code only suitable for english language speaking users. IBM and Apple expanded the amount of space reserved for the character codes to 8-bits, equivalent to 1 byte.
8. ASCII enables manufacturers to produce components that are assured to operate correctly in a computer. ASCII was established to ASCII makes it possible achieve compatibility for humans to interact between various types of with a computer. It alsodata processing equipment enables users to purchase making it possible for the components that are components to compatible with their communicate with each computer configurations other successfully. Functions of ASCII codes
9. When you press a key, for example the letter D on your keyboard, the electronic signal is sent to the CPU for the computer to process and store in memory.In this example, Every character is the letter D is converted to its converted to corresponding 01000100. binary form. When the computer is finished The computer the processing the processes the byte, the software letter as a installed in the byte., which system convert actually a series of the byte back on and off of which is then electrical states. displayed in the screen.
10. Text • You can enter data by pressing the keys on the keyboardGraphic • A digital camera allows you to take pictures and store the photographed images digitallyAudio • Input the speech, music and sound effects entered into the computerVideo • Input of motion images captured into the computer by special input devices.
11. Central Processing Unit (CPU) Ports Expansion and SlotConnectors Components of motherboard Expansion RAM Slot Cards
12. Information anddocument are stored in computer storage sothat it can be retrieved whenever they are needed later on. Storage Computer storage isthe holding of data in an electromagnetic form for access by a computer processor.
13. Function of Computer StorageHelp users store programs and data to be used at a later time Stores instructions from a computer programs
14. Definition of operating system Set of programs that schedule tasks, allowcates storage and presents a default interface to the user between applications.Function of the operating system are : Starting a computer Providing a user interface Managing data and programs Managing memory Configuring devices
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Thursday, 18 August 2016
Unicode is a computing industry standard for the consistent encoding, representation, and handling of text expressed in most of the world's writing systems. Developed in conjunction with the Universal Coded Character Set (UCS) standard and published as The Unicode Standard, the latest version of Unicode contains a repertoire of more than 128,000 characters covering 135 modern and historic scripts,
as well as multiple symbol sets. The standard consists of a set of code
charts for visual reference, an encoding method and set of standard character encodings, a set of reference data files, and a number of related items, such as character properties, rules for normalization, decomposition, collation, rendering, and bidirectional display order (for the correct display of text containing both right-to-left scripts, such as Arabic and Hebrew, and left-to-right scripts).[1] As of June 2016, the most recent version is Unicode 9.0. The standard is maintained by the Unicode Consortium.
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