Government College, Mirpur Faculty of Literature and Linguistics Department of English Assignment no: 01 Name: Amina Sani Roll no: 05 Course name: Introduction to ICT Skills Course code: ICTS-1105 Semester: 01 Submitted to: Sir Sufyan Submitted by: Amina Sani Date: 4 January, 2022 Session: 2021-2025 Question: 01 How data is represented in computer? Answer We all have seen computers do seemingly miraculous things with all kinds of sounds, pictures, graphics, numbers and text. It seems that we can build a replica of parts of our world inside the computer. We might think that this amazing machine is also amazingly complicated - it really is not. In fact, all of the wonderful multimedia that we see on modern computers is all constructed from simple ON/OFF switches -millions of them- but really nothing much more complicated than a switch. The trick is to take all of the real-world sound, pictures, numbers etc. data that we want in the computer and convert it into the kind of data that can be represented in switches. Computers are electronic machines. The computer uses electricity, not mechanical parts, for its data storage and processing. Electricity is plentiful moves very fast through wires and electrical parts get much lesser energy than mechanical parts. The computer does have some mechanical parts, like its disk drives, but the internal data processing and storage is electronic, which is fast and reliable. Electricity can flow through switches, if the switch is closed, the electricity flows. If the switch is open, the electricity does not flow. To process data in computer, we need a way to represent the data in switches. Computers do this representation using binary coding system. Binary system: Binary is a mathematical number system, usually 0 and 1, which represent the two states of computer, ON and OFF. 0 is for OFF and 1 is for ON. Unlike in decimal numbers where the place value goes up in factors of ten, while in binary system, the place value increases by the factor of 2. Binary numbers are written as X2. Reasons for use of binary system in computers It has proved difficult to develop devices that can understand natural language directly due to the complexity of natural languages. However, it is easier to construct electric circuits based on binary or ON and OFF logic. All forms of data can be represented in binary system format. Other reasons for the use of binary system are that digital devices are more reliable, small and use less energy as compared to analog devices. The terms bits, bytes, nibbles and words are used widely in reference to computer memory and data size. Bits can be defined as either a binary, which can be 0 or 1. It is the basic unit of data or information in digital computers. Byte can be defined as a group of bits, usually 8 bits, to represent a character. A byte is considered as the basic unit of measuring memory size in computer. Nibble is half a byte, usually grouping of 4 bytes. Word is formed by two or more bits. Word length is used as the measure of the number of bits in each word. For example, a word can have a length of 16 bits, 32 bits, 64 bits etc. Types of data representation Computers not only process numbers, letters and special symbols but also complex types of data such as sound and pictures. However, these complex types of data take a lot of memory and processor time when coded in binary form. This limitation necessitates the need to develop better ways of handling long streams of binary digits. Higher number systems are used in computing to reduce these streams of binary digits into manageable form. This helps to improve the processing speed and optimize memory usage. Data representation in digital computers Data and instructions can’t be entered and processed directly into computers using human language. Any type of data should be first converted into binary form. Data representation in digital circuits Electronic components, such as microprocessor, are made up of billions of electronic circuits. The availability of high voltage ON in these circuits in interpreted as ‘1’ while a low voltage OFF is interpreted as ‘0’. This concept can be compared to switching ON and OFF an electronic circuit. When the switch is closed, the high voltage in the circuit causes the bulb to light ‘1 state’. On the other hand while the switch is open, the bulb goes OFF ‘0 state’. This forms a basis for describing data representation in digital computers using binary numbers. Data representation on magnetic media The laser beam reflected from the land is interpreted as 1. The laser entering the pot is not reflected, interpreted as 0. The reflected pattern of light from the rotating disk falls on a photoelectric detector that transforms the patterns into digital form. The presence of a magnetic field in one direction on magnetic media is interpreted as 1; while the field in the opposite direction is interpreted as 0. Magnetic technology is mostly used on storage devices that are coated with special magnetic materials such as iron oxide. Data is written on the media by arranging the magnetic dipoles of some iron oxide particles to face in the same direction and some others in opposite direction. Data representation on optical media In optical devices, the presence of light is interpreted as ‘1’ while absence by ‘0’. Optical devices use this technology to read or store data. For example a CD-ROM. Question: 02 Write a note on storage devices. Answer Storage devices: A storage device is any type of computing hardware that is used for storing, porting or extracting data files and objects. Storage devices can hold and store information both temporarily and permanently. They may be internal or external to a computer, server or computing device. The data and file are stored in an organized way to access it more easily. Without storage system in computers, computers may not work as expected. Every storage device needs a storage unit to work. The information or data can be text files, videos, programs, documents, images and applications. Types of storage devices There are three types of storage devices: 1. Primary storage devices 2. Secondary storage devices 3. Tertiary storage devices Primary storage devices: Generally smaller in size, primary storage devices are designed to hold data temporarily and are internal to the computer. They have the fastest data access speed. These types of devices include RAM and cache memory. Secondary storage devices: Secondary storage devices usually have larger storage capacity and they store data permanently. They can be either internal or external to computer. These types of devices include the hard disk, the optical disk drive and USB storage device. Tertiary storage devices: It enables with robotic mechanism that help to insert and remove massive storage media into storage device as per the system’s needs. Tertiary storage is used to move media in between their long-term storage locations and available drives without human intervention. Examples are magnetic tapes, optical discs and optical tapes etc. Storage devices of computer 1. USB Drive A USB Drive is a small, light, ultra-portable storage device compatible with Windows, MAC AND Linux. The pen drive replaced floppy drives and became one of the most popular portable data storage devices on the market. It is small, lightweight, practical and can be easily carried anywhere instead of an optical drive or a traditional hard disk drive. These types of computer storage devices are used to store documents, photos, music files and videos. Its range is from 2 GB to 1 TB. 2. Hard Disk Drive The short for of Hard Disk Drive is HDD. A HARD DRIVE is a computer-accessible storage device based on the magnetic record technology. They are used in the vast majority to store all types of small or big files or data of computers, storing backup copies of data, like file storage on digital computers. A round-shaped disk consists inside of a hard disk, which rotates. The faster the speed of turns, the faster it can store or read data. The speed of hard disk is measured in RPM, i.e. Revolution Per Minute. Most hard disks are of 5400 RPM and some of 7200 RPM. 7200 RPM disk is faster than 5400 RPM disk. 3. Solid State Drive It is a bit similar to hard disk drive, but it has storage capacity more than a hard disk drive and more sophisticated device. It uses the integrated circuit memory made of semiconductor technology like RAM, but it is used to store data permanently. 4. Memory Card A memory card is also known as a Flash Memory Card or SD Card (Secure Digital Card), is an external storage medium that allows us to save and delete information. We use memory card as secondary storage for our devices to store data such as photos, videos, file etc. Devices that typically use memory cards include DSLR cameras, smart phones, printers etc. The amount of storage capacity can vary depending on type of memory card. Mostly cards range in size from 4 GB to 256 GB. 5. CD A ‘Compact Disk’ is abbreviation of CD. It is flat, round, optical storage medium used to store audio. They were made to replace floppy disks. It has two sides; one side contains data while the other side reads data. Discs can store up to 700 MB of data, which equates to approximately 80 minutes of audio. Mini-discs can keep 24 minutes audio files. 6. DVD A complete form of DVD is Digital Video Disk or Digital Versatile Disk. DVDs are similar to CDs. A DVD can be double-layered and double-sided. This allows users to store data up to 17.08 GB on a dual-layer, double-sided disc. A single-layer, single-sided disc contains approximately 4.7 GB of data. 7. Floppy Disk Floppy disk is another storage device. The first floppy was created in 1969; the same year internet was launched. These magnetic disks are fragile and flexible enclosed in a square or rectangular plastic coating. The floppy disk stores a small amount of data. The floppy disk was the primary portable storage medium for data and programs before CD’s rise in popularity. Question: 03 Write a note on Computer and ICT. Answer What is Information and Communication Technologies (ICT)? Diverse set of technological tools and resources used to transmit, store, create, share or exchange information. These technological tools and resources include computers, the Internet (websites, blogs and emails), live broadcasting technologies (radio, television and webcasting), recorded broadcasting technologies (podcasting, audio and video players and storage devices) and telephony (fixed or mobile, satellite, Visio/video conferencing) etc. ICT systems used in everyday life ICT systems are often confused with computers; however they are not the same thing. Computer refers to the hardware that forms parts of an ICT system. The ICT refers to the overall setup, consisting of software, hardware, data and the people that use it. It commonly includes communication technology, such as internet technology. Information and Communication Technology (ICT) is a field related to computers and communication networks. It can also be in the form of audiovisuals, for example, film and digital productions. Digital technologies use data such as text, numbers, images, sounds and videos. Computers use this data to show information. In the past, these technologies used to be separate systems, but recently, these technologies have become almost ‘one’. Computers have become more like smart phones and smart phones have become more like computers. ICT is a field that looks at all these technologies as one. An ICT system depends on computers, data and people to make the system work. For ICT system to work correctly, they need to receive, store, retrieve, manipulate and transmit data. Data is often in the form of text, numbers, sounds and images. Computers and ICT Computers are electronic devices that receive data, manipulate the data and then turn it into useful information, before storing it and sending it to someone, or somewhere, to be acted upon. Computers consist of four functions basically 1. 2. 3. 4. Input Storage Processing Output These four things are combined to make a computer work. For a computer to function properly, it must consist of both hardware and software, which both depend on each other. Without software, the hardware of a computer will have no function and vice versa. Hardware means the physical components of a computer, also referred to as equipments of computers. Software means programs or applications and consists of a list of instructions in a computer language that instructs the computer on what to do. Importance of computers Internet The World Wide Web, internet and email revolutionized the way individuals communicate with each other. Rather than waiting days or weeks to see information, we can now view all information at the speed of light. Email has fundamentally transformed how people share information and conduct business based on the speed and flexibility it offers. Computers can process data at approximately 20 million bytes per second so it is easy for us to download and instant display almost ant text email. VOIP and Video Chat Voice Over Internet Protocol or VOIP replaced the need for landline telephones in many instances. These lines can provide instant phone communication over the internet and often are cheaper than fixed phone lines. They also provide the ability to conduct video chats to see whom you are speaking with. VOIP platforms also store contact details for easy accessibility and dialing. Social Networking Social networking sites including Face Book, Twitter and LinkedIn allow users to rapidly generate content for people in their network to view. Rather than sending individual notes, social networking provides constant streams of updates and information. These computer tools have taken communication a step further than email due to their ability to instantly communicate life and status updates to an entire network of people who can respond and comment to such notes in real time. Routing While it is not a personal computer, routers are types of computers used to direct communication traffic. They are crucial to the efficient and correct distribution of calls, emails or internet traffic. Routers take ‘packets’ of electronic data and send them in the direction to connect with the intended person. They can be used in home but are also held in central data warehouses where hubs of traffic are routed in the same place.