Computer Basics: What is a Computer?

Introduction

The computer is a device that is bonded to the lives of the 21st-century people. That bond could not be broken because it plays a major role in our lives and most of our day to day activities cannot be accomplished without using a computer. It is now not on the list of thing that we need but on the list of things we should have.

What is a computer?

There are so many different ways to introduce a computer. In many resources, they give us many definitions about this magical device (resources: – internet, books).
Environments that have computer systems
This world we live in a giant computer system. Which have small computer systems helping it to run, we can set them as:-
• Business field
• Medical field
• Entertainment field
• Education field
• Etc.

Emerging technology cloud computing plays a major role in these fields now. Cloud computing is a form of Internet-based computing that provides shared computer processing resource and data to computers and other devices on demand.

Business field

A computer has tremendously improved the way businesses operate in their respective industries. Technology has advanced so remarkably that those who are not using the computer in their business are at a major disadvantage against their competitors. Businesses use many different types of computer to fulfill their daily targets. (Example:- desktop computers, laptops, tablets, smartphones).
Clouds computing in business field have so many advantages. With these networked technology companies can store data more easily and cloud computing is more cost effective. It allows you to set up what is essentially a virtual office to give you the flexibility of connecting to your business anywhere, anytime.
1. Some advantages
• Cloud computing allows employees to be more flexible in their work. For example, you have the ability to access data from home, on holiday, or via the commute to and from work (providing you have an internet connection). If you need access to you data while you are off-site, you can connect to your virtual office, quickly and easily.
• Avoids large capital expenditure on hardware and upgrades
• Monitoring your infrastructure 24/7
• A cloud environment means that the security of your documents no longer rests on your shoulders.

Because companies don’t have to purchase equipment’s and build out and operate a data center, they don’t have to spend significant money on hardware, facilities, utilities and other aspects of the operation. Ever-changing business requirements mean that your IT infrastructure has to be flexible. Monitoring your infrastructure 24/7 is time-consuming and expansive when you have a business to run. A managed cloud solution means that your hosting provider is doing this for you.in addition to monitoring your infrastructure and keeping your data safe, they can provide creative and practical solutions to your needs, as well as expert advice to keep your it infrastructure working efficiently as your needs evolve.

Medical field

In these days computers are an essential part of the medical field. This medical field is not a small field is has so many categories in it so this device the computer has to play huge roles in the medical field. Cloud computing technology is on the rise in the medical industry. Big data has become an overwhelming challenge for many health organizations and the cloud allows providers to save money by minimizing in-house storage needs. The information also becomes more accessible from various locations, and even if something happens on-site, the data is still preserved. One of the most intuitive benefits of cloud computing for healthcare is that the cloud makes it far easier to archive and use patient records and medical images. Many physicians find cloud computing makes it easier to collaborate and offer care as a team. Through mobile devices, video conferencing, and applications built specifically for healthcare organizations, the cloud speeds things up and allow better communication at a distance.

Entertainment field (gaming)

The entertainment sector is a huge umbrella term wherein you would find a large number of sub-industries devoted to entertainment. It is the most happening industry that always provides fun, entertainment, enjoyment and amusement to people.
With the technology, gaming has come to the peak level. Cloud computing provides new opportunities to the gaming industry and solves the prevailing issues as well. The technology almost embraces the sector and has much more to contribute to the evolvement if the growing gaming industry. The application of cloud computing is not only beneficial for enterprises but also for the consumers. With the modern gaming, we must get us an expansive computer. But with cloud gaming, we wouldn’t need to upgrade our pc or console. We can just use our existing hardware. Some games may require a download 10GB, 20GB, or even more before you can play them. Cloud gaming would allow you to start playing games instantly; as the server has the game installed and can start playing it immediately.

Education

Computers act a major part of the education in present. In fact, there is a huge relationship between education and computer. It’s no secret that university-level textbooks are expensive. As a result, many students are simply refusing to buy them. Cloud-based textbooks can solve this problem as digital content is significantly less expensive than printed content. This levels the playing field so that lower-income students can have the same access to quality leaning materials as their higher-income counterparts. There was a time when, to use files (word processing files, spreadsheets, etc.) on different computers, you needed to save your files on thumb drives or CD-ROM disk. The drive or disk then traveled around with you so that you could load your information onto other computers while holding your breath until the document or PowerPoint slide was actually retrieved! Not anymore. The safety, stability, and ease-of-use of cloud computing in education are resulting in widespread adoption in education institutions of all size and types. With cloud computing redundancy, there is no longer the need to save digitally and in paper format. Cloud computing systems are regularly backed-up, so the chances of losing content quite small.
Cloud-based applications can be run on. Internet browsers, but most are compatible with mobile devices as well. This means that schools and students do not necessarily need to own expensive computers.

Task 2

From what is a computer system made of?

A system is a collection of elements that work together to achieve a comment target. There is no difference between this and the computer system. A computer system is made up of the CPU, operating system, and peripheral devices. All the laptops computers, desktop computers, network servers, minicomputers, and mainframes are computer systems.
A simple computer system can be drawn from
• Input devices
• Output devices
• Control unit
• Arithmetic logic unit
• Memory
• External storage

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1. Hardware
Hardware refers to the physical components of a computer system such as monitor, mouse, keyboard, etc. computer hardware can be classified into two sections.
• Peripheral device
• Devices inside the system
A computer peripheral is a device that is connected to a computer but is not a part of the core computer architecture. The core elements of a computer are the central processing unit, power supply, motherboard and the computer case that contains those three components. Technically everything else is considered a peripheral device. The peripheral device can be external or internal
Types of peripheral devices and some examples
• Input devices (mouse, keyboard)
• Output devices (monitor, printer)
• Storage devices ( hard drive or flash drive)
Basic hardware components
• Central processing unit
A central processing unit (CPU) is the electronic circuitry within a computer that carries out the instructions of a computer program.it runs the operating system and applications, constantly receiving input from the user or active software program. It processes the data and produces output, which may store by an application or display on the screen. The enter speed of the computer depends on the CPU.

CPU has 4 main parts

Arithmetic and logic unit (ALU): which performs arithmetic and logic operations.
Control unit (CU): which tell the computer’s memory, ALU, and input and output devices on how to respond to a program’s instructions.
Register:
Cache memory: store program instructions that are frequently referenced software during operations.
One of the main things that we must think of this CPU is the speed. The CPU’s speed is mainly determined by its internal clock speed. The clock rate of the first generation of computers was measured in hertz (Hz) or kilohertz (KHz), but in the 21st century the speed of modern CPU is commonly measured in gigahertz (GHz)
1 Hz = 1 cycle
1000 Hz = 1 KHz
1000 KHz = 1 MHz
1000 MHz = 1 GHz
Simply 1GHz is one billion cycles per second
• Memory
When a computer is working, it needs a working memory to hold the data and store the programs which are currently running. This working memory can be called the primary memory or the main memory. This memory can be divided into two parts
1. RAM
2. ROM

RAM

RAM stands for Random Access Memory. It is the main working memory within the computer. RAM allows storing information and retrieving them on the computer when a user wants. RAM requires a flow of electricity to retain data it loses the data or information when the user turns the computer off. Therefore the information stored in the RAM is volatile.

ROM

ROM stands for reading Only Memory. ROM is a special type of memory chip it contains read-only programs which help in the boot up the computer. It’s used to store the start-up instruction for a computer, also known as the firmware. Which is located on the motherboard.
• Input devices
An input device is any hardware device that sends data to a computer allowing you to interact with and control the computer
Example:- keyboards, mouse, scanners, digital cameras, joysticks, touchpad, microphone, trackball, webcam, barcode reader, light pen, optical mark reader and etc.

Keyboard

A keyboard is an essential input device to the computer. This can be used for entering information into computer. Keyboard allows inputting letters, numbers, different types of numbers and simultaneous key presses can produce actions or execute computer commands.
A normal computer keyboard is composed of around 110 keys and there are 4 major keyboard layouts as follows.
 QWERTY
 AZERTY
 QWERTZ
 HCESAR

Mouse

A mouse is the main input device in any type of computer. Moving a mouse along a flat surface can move the on-screen cursor to different items on the screen. Items can be move or selected by pressing the mouse button (clicking). There are many different types of mice. Commonly used type is “optical mouse”
Some types of mice
 Optical mouse
 Wireless mouse
 Trackball
 Glick mouse
 Mechanical mouse

Scanner

A scanner allows scanning printed materials and converting it into a format that can be used within the computer. The 4 common scanner types are
 Flatbed
 Sheet-fed
 Handheld
 Drum scanners

Light pen

This device is another input component which can be used for entering data. A light pen allows pointing out an area on a screen or drawing on the screen in a similar way to a touchscreen.
• Output
An output device is any kind if the peripheral device which can use for receiving data from the computer.
Example: – monitor, printer, speakers and etc.

Monitor

A computer monitor is a display adapter that displays information processed by the computer video card. There are different types of monitors
 CTR (cathode ray tube )
 LCD (liquid crystal display)
 Etc.

Printer

A printer is a peripheral device which can represent graphics or text on paper or similar physical media. Printers vary in size, speed, and cost. There is the number of different printers available in the market. Example: – laser printer, inkjet printer, dot matrix printer,
Mainly they are categorized into 2 groups
 Impact printer: – this printer type works by banging a head or needle against an ink ribbon to make a mark on the paper. Example: – dot matrix printer.
 Non-impact printer: – use tiny jets to spray ink onto the paper. Example:- inkjet printer

Speakers

Speakers are the devices which use to receive sound from the computer. They receive audio input from the computer sound card and produce audio output in the form of sound waves.
• Storage devices
Computer storage is measured in bytes, Kilobytes (KB), Megabytes (MB), Gigabytes (GB), and Terabytes (TB)
1 KB = 1000 bytes
1 MB = 1000 KB
1GB = 1000 MB
1 TB 1000 GB
There are 4 types of hard disks drives
 Parallel advanced technology attachment (PATA)
 Serial ATA (SATA)
 Small computer system interface (SCSI)
 Solid state drive (SSD)

Internal hard disk

An internal hard disk is the primary storage device located inside a computer system. Most desktop computers have several internal hard drives allowing them to provide greater data storage.

External hard disk

An external hard disk is a portable storage device that can be attached to a computer through a USB, wirelessly and etc. external hard drives typically have high storage capacities.
speed capacity
Internal hard disk
External hard disk
Zip disk slow 100 MB, 250MB, 750MB
Floppy disk Very slow 1.44 MB
CD from disk 700MB
DVD drive 407GB

And there are many more storage devices

3. Software

The software is a collection of programs or applications, which contain the instructions that make the computer work. Actually without software computer would be useless. Anything that can be stored electronically is software. The software is a wide and complicated area in computer science. The software is often divided into two main categories.
1. System software
2. Application software
System software
It is used to control the computer hardware and to provide and maintain a platform for running application software. The operating system (OS) is the best- known example of system software. The OS manages all other programs on the computer.

Application software

Application software is a set of computer programs that do real work for a user. These software’s follow the user to perform a group of functions, tasks, and activities in a particular environment, for Examples MS office adobe collection, etc.

Why are different types of computer needed?

As it is mentioned above, the computer is a magical device invented by humans. If there is anything equal to the human brain, it will be the modern computers. When considering the performance of computers, there different types of computers for different purposes. As a result, now there are various types of computers in the computer spectrum. Therefore computer can be satisfying the users who need to execute different requirements. They are
 Personal computers
 Workstation computers
 Minicomputers
 Mainframe computers
 Supercomputers
Each computer category has there on special features and attributes

Supercomputers

Today the most powerful and the fastest computers are the supercomputers. Supercomputers are very large and very expensive computers. Therefore some supercomputers can even occupy an entire building. Performance of a supercomputer is measured in FLOPS (floating-point operations per second) as of 2015 there are supercomputers which can perform up to quadrillions of FLOPS, measured in PETAFLOPS. Supercomputers play an important role in the field of computational science and are used for a wide range of tasks in various fields like weather forecasting, climate research, nuclear weapons testing and etc. As of June 2017 the fastest supercomputer in the world of the Sunway TaihuLoght it tops the ranking in the Top500 supercomputers list, with a top speed of 93 (PETAFLOPS)

Mainframe computers

Although not as powerful as supercomputers, mainframe computers are big powerful, expensive computers used in the background of most large organizations for critical applications, bulk data processing and many more. Mainframes are designed to handle very high volume input and output and emphasize throughput computing. Nearly all mainframes have the ability to run or host multiple operating systems.in the computing spectrum, the supercomputers are at the top of the line and mainframe computers are just below the supercomputers. However, the mainframe can be more powerful than supercomputing when considering the support of concurrent programs. But supercomputers can run a single program faster than a mainframe computer. The speeds of these computers are measured in MIPS (million instructions per second).

Minicomputers

A minicomputer is a type of computer that possesses most of the features and capability of a large computer but is smaller on physical size. Minicomputers are also called “mid-range computers”. Minicomputers are mainly used as small or mid rang server operating business and scientific applications. Minicomputers may contain one or more processors, supports multiprocessing and tasking, and are generally resilient to high workloads. Although they are smaller than mainframe and supercomputers, minicomputers are powerful than personal computers and workstations.

Workstation computers

A workstation computer is a computer intended for individual use that is faster and more capable than a personal computer but less advanced than a minicomputer. Workstations and applications designed for them are used by small engineering companies, architects, graphic designers, and departments requiring a faster microprocessor, a large amount of RAM and special features such as high speed graphics adapters. However, these computers are designed for the single user.

Microcomputers

The microcomputers are widely used and the fastest growing computers in the 21st century. These are the cheapest among all the computer type. The term “microcomputer” was introduced with the advent of single chip microprocessors. A microcomputer is a complete computer on a smaller scale and is generally a synonym for the more common term, a personal computer (PC). These computers include
• Desktop computers
• Game consoles
And the separate call is that of mobile devices
• Laptops, notebooks, and palmtop computers
• Tablets computers
• Smartphones, smartbooks, and PDAs
• Handheld game consoles