Category: computer Fundamentals

Computer Fundamentals Tutorial PDF Version Quick Guide Resources Job Search Discussion Computer is an advanced electronic device that takes raw data as an input from the user and processes it under the control of a set of instructions (called program), produces a result (output), and saves it for future use. This tutorial explains the foundational concepts of computer hardware, software, operating systems, peripherals, etc. along with how to get the most value and impact from computer technology. Audience This tutorial has been prepared for beginners as well as advanced learners who want to deal with computers. The tutorial is also very useful for undergraduate students of computer science, engineering, business administration, management, science, commerce and arts, where an introductory course on computers is a part of curriculum. After completing this tutorial, you will find yourself at a moderate level of expertise in the knowledge of computer basics from where you can take yourself to the next level. Prerequisites Knowledge of computers is not a prerequisite to follow the contents of this tutorial. This tutorial assumes no background in Computers or Computer programming. Print Page Previous Next Advertisements ”;

Computer – Central Processing Unit (CPU) ”; Previous Next Central Processing Unit CPU stands for Central Processing Unit; it is also known as “the brain of the computer”. A CPU is a primary component of a computer that performs most of the processing and controls the operation of all components running inside a computer. The key components of a CPU are the Control Unit, ALU and Memory. The alignment and integration of key components are included in the above figure. Components of CPU Control Unit (CU) ALU (Arithmetic Logic Unit) Memory or Storage Unit Registers Control Unit As its name implies, a control unit acts as the “brain” of the CPU. A major role of a control unit is to manage and execute instructions to perform the tasks specified by a computer program. v. A CPU executes instructions by fetching them from memory, decodes them, and then executes them. So, it plays a vital role in fetch-decode-execute instructions. Functions of Control Unit Instruction Fetch − A CU fetches instructions from RAM (Random Access Memory). Instruction Decoding − It decodes the fetched instructions to operate. Instruction Execution − A CU sends control signals to perform operations like ALU for arithmetic and logical operations. Control Flow Management − It controls flow by updating the programme counter. Exception Handling − A control unit effectively manages exceptions and interruptions like hardware failures, system calls, and external events, by appropriately diverting the control flow of the CPU to the planned procedure for managing such exceptions. Synchronization − A CU plays a crucial role in facilitating the coordination of instruction execution across several cores. Arithmetic Logic Unit (ALU) The Arithmetic Logic Unit (ALU) is a component that has been extensively optimised and engineered to do multiple tasks concurrently. It is commonly built to execute operations speedily. It works in conjunction with other CPU components, such as registers, memory, and control units, to execute complex instructions. Functions of an ALU Arithmetic Operations − The ALU can perform basic arithmetic operations. Logic Operations − The ALU can also perform logical operations like AND, OR, NOT, XOR, and bit-shifting operations. Memory Unit A memory is a hardware component which is used to store and access the data whenever required. Majorly; computer memory is categorised into two parts Primary Memory (RAM) and Secondary Memory (Hard Disk). RAM is used for short-term, fast data access and is essential for active program execution. On the other hand, storage or secondary memory provides permanent data storage. Hence, memory and storage units both are critical components of a computer system. Functions of memory Primary Memory RAM is also known as primary or temporary memory; it is a type of volatile memory used for temporarily storing data. The contents inside the RAM are erased when the computer’s power gets off or restarted. RAM is actively used for program or instruction execution. Once we start the computer; system necessary files, programs and operating system files are loaded into the RAM for the smooth running of the computer. The more RAM a computer has, the better it can handle multitasking and the faster it can run applications since data can be accessed more quickly. Storage (Hard Drives, SSDs, Flash Drives, etc.) Storage devices are used to store the data permanently, even when the computer is powered off. They are non-volatile; the data remains intact even when the power is turned off or the system restarts. The most popular and commonly used storage devices are Hard disks (HDs), Solid-State Drives (SSDs), USB flash drives, and optical disks (e.g., DVDs), pen drives. The data storage capacity of these devices in gigabytes (GB) to terabytes (TB) and more, depending on the type and size of the storage device. Functions of the CPU The key functions of a CPU are as follows − The CPU performs arithmetic and logic operations. It directs the operation of the processor. It directs Input and output units that how to respond to the instructions that have been communicated to the processor. A CPU contains registers which are considered small storage locations within the CPU to hold data temporarily during execution of a program. A CPU executes instructions by fetching them from memory, decodes them, and then executes them. Print Page Previous Next Advertisements ”;

Classification of Computers ”; Previous Next A computer can be classified based on its size, capacity, and purpose. The following diagram illustrates different types of computers as per their size, capacity, and purpose. Computer”s classification based on Size As per the size, a computer can be broadly classified as follows − Micro Computer Mini Computer Mainframe Computer Super Computer Micro Computer Microcomputers, also known as personal computers (PCs), are a type of computer designed for individual use. They are distinguished by their compact dimensions, small size, processing power, compatibility, internet connectivity, portability, low price, and versatility. In the 1970s and 1980s, microcomputers gained popularity and became more popular in the modern computing era. Fig: Micro Computer Size − Microcomputers are small in size. These are portable. Example − Some of the popular microcomputers are laptops and desktops, standard PCs, mobile phones, and notebooks. Why microcomputer ? Microcomputers have become an important part of modern life. They have had a big impact on society, companies, education, and related areas. Uses of Microcomputers − Microcomputers are most widely used in education and learning, entertainment and media, innovation and creativity, research and science, healthcare and medicine, home automation, remote work, and e-commerce and online shopping. Minicomputer A minicomputer is a type of computer that is smaller in size than large computers. It possesses all the capabilities of a large computer. Hence, it is a midsize multi-processing system capable of supporting up to 250 users simultaneously. Fig: Mini Computer Size − Its size falls between mainframes and microcomputers. It is larger than mainframe computers and smaller than microcomputers. Example − Some of the popular minicomputers are the PDP-11, IBM”s AS/400e, Honeywell 200, and TI-990. Why a Mini Computer? Mini computers are also known as mini PCs or small-form-factor (SFF) computers. These have impressive computing capabilities, high performance, connectivity options, portability, and versatility features. Uses of Minicomputers − Minicomputers are most widely used in scientific computations, engineering, business transaction processing, file handling, and database management. Mainframe computer The mainframe is very large and is an expensive computer capable of supporting hundreds or even thousands of users simultaneously. The mainframe executes many programmes concurrently and supports simultaneous execution of programmes. Fig: Mainframe Computer Size − Mainframe computers can vary in size; their size generally depends on their specifications and the specific model being considered. Example − Some of the popular mainframe computers are IBM zSeries mainframes (BM z14 and IBM z15), Unisys ClearPath, Fujitsu GS21 Series, and Hitachi VOS3. Why a mainframe computer? The processing capacity of mainframes is frequently measured in MIPS (million instructions per second) or other units. This enables them to process a large volume of transactions and perform extensive data processing. Uses of the Mainframe − Mainframe computers are most widely used in finance, government, healthcare, and more. Supercomputer A supercomputer is a special type of computer that is more powerful and capable of high-performance computing. It is specifically designed to compute complex and intensive tasks that regular computers cannot do efficiently. Size − Supercomputers can vary in size, from small clusters of computers to massive installations. A supercomputer may contain 10, 100, 1000, or more computers that all work together. Fig: Super Computer Example − Some of the popular supercomputers are Fugaku, Google Sycamore, Baidu”s quantum supercomputer, and Sierra. Why Supercomputer? A supercomputer”s processing speed is exceptional and can perform billions of calculations per second. Multiple processors work in parallel mode to execute tasks, which makes processing powerful. Supercomputers are specially built using specialised hardware like GPUs (Graphics Processing Units) or TPUs (Tensor Processing Units), which are used in graphics rendering or machine learning tasks. Supercomputers represent the pinnacle of computing power, and these are very expensive and are employed for specialised applications. Uses of the Supercomputer − Supercomputers are most widely used in scientific research, data analysis, weather forecasting, scientific simulations, graphics, fluid dynamic calculations, nuclear energy research, electronic design, and the analysis of geological data. Computer”s classification based on Capacity As per the capacity, a computer can be broadly classified as follows − Analog Computer Digital computer Hybrid computer Analog Computer A computer that uses physical means like mechanical or hydraulic components to do the computation rather than electronic circuits is called an analogue computer. These computers work with continuous data and can manage physical quantities efficiently. They are particularly good at solving differential equations and simulating dynamic systems. Fig: Analog computer In lieu of numbers, an analogue computer performs arithmetic operations based on measurable quantities, such as mechanical movement or the rotation of gears. In analogue computers, data is processed as continuous signals for its operation, whereas in digital computers, data is transmitted as discrete signals (or discontinuous signals). Digital Computer A digital computer is a type of computer that represents and processes data using discrete, distinct values. Fig: Digital computer In digital computers, data is processed using binary numbers 0 and 1. These computers are designed to perform arithmetic calculations and complex data processing and manipulation. The main components of a digital computer are input, processing, and output. Hybrid Computer A hybrid computer is a type of computer system that integrates the features and capabilities of both analogue and digital computers. This integration allows the hybrid computer to perform various tasks efficiently by leveraging the strengths of both digital and analogue technologies. Fig: Hybrid computer The main components of a hybrid computer are the analogue and digital components − Analog Component − Analogue components in a hybrid