SOFTWARE CONCEPT

As you know, the hardware devices need user instructions to function. A set of instructions that achieve a single outcome are called program or procedure. Many programs functioning together to do a task make a software.

For example, a word-processing software enables the user to create, edit and save documents. A web browser enables the user to view and share web pages and multimedia files. There are two categories of software 

•  System Software
•  Application Software
•  Utility Software

Let us discuss them in detail.

System Software

Software required to run the hardware parts of the computer and other application software are called system software. System software acts as interface between hardware and user applications. An interface is needed because hardware devices or machines and humans speak in different languages.

Machines understand only binary language i.e. 0 (absence of electric signal) and 1 (presence of electric signal) while humans speak in English, French, German, Tamil, Hindi and many other languages. English is the pre-dominant language of interacting with computers. Software is required to convert all human instructions into machine understandable instructions. And this is exactly what system software does.

Based on its function, system software is of four types 

•  Operating System
•  Language Processor
•  Device Drivers

Operating System

System software that is responsible for functioning of all hardware parts and their interoperability to carry out tasks successfully is called operating system (OS). OS is the first software to be loaded into computer memory when the computer is switched on and this is called booting. OS manages a computer’s basic functions like storing data in memory, retrieving files from storage devices, scheduling tasks based on priority, etc.

Language Processor

As discussed earlier, an important function of system software is to convert all user instructions into machine understandable language. When we talk of human machine interactions, languages are of three types 

• Machine-level language: This language is nothing but a string of 0s and 1s that the machines can understand. It is completely machine dependent.

•  Assembly-level language: This language introduces a layer of abstraction by defining mnemonics. Mnemonics are English like words or symbols used to denote a long string of 0s and 1s. For example, the word “READ” can be defined to mean that computer has to retrieve data from the memory. The complete instruction will also tell the memory address. Assembly level language is machine dependent.

•  High level language: This language uses English like statements and is completely independent of machines. Programs written using high level languages are easy to create, read and understand.

Program written in high level programming languages like Java, C++, etc. is called source code. Set of instructions in machine readable form is called object code or machine code. System software that converts source code to object code is called language processor. There are three types of language interpreters

•  Assembler: Converts assembly level program into machine level program.

•  Interpreter: Converts high level programs into machine level program line by line.

•  Compiler: Converts high level programs into machine level programs at one go rather than line by line.

Device Drivers

System software that controls and monitors functioning of a specific device on computer is called device driver. Each device like printer, scanner, microphone, speaker, etc. that needs to be attached externally to the system has a specific driver associated with it. When you attach a new device, you need to install its driver so that the OS knows how it needs to be managed.

Application Software

A software that performs a single task and nothing else is called application software. Application software are very specialized in their function and approach to solving a problem. So a spreadsheet software can only do operations with numbers and nothing else. A hospital management software will manage hospital activities and nothing else. Here are some commonly used application software 

•  Word processing
•  Spreadsheet
•  Presentation
•  Database management
•  Multimedia tools

Utility Software

Application software that assist system software in doing their work is called utility software. Thus utility software is actually a cross between system software and application software. Examples of utility software include 

•  Antivirus software
•  Disk management tools
•  File management tools
•  Compression tools
•  Backup tools

CLASSIFiCATION

Historically computers were classified according to processor types because development in processor and processing speeds were the developmental benchmarks. Earliest computers used vacuum tubes for processing, were huge and broke down frequently. However, as vacuum tubes were replaced by transistors and then chips, their size decreased and processing speeds increased manifold.

All modern computers and computing devices use microprocessors whose speeds and storage capacities are skyrocketing day by day. The developmental benchmark for computers is now their size. Computers are now classified on the basis of their use or size.

•  Desktop
•  Laptop
•  Tablet
•  Server
•  Mainframe
•  Supercomputer

Let us look at all these types of computers in detail.

Desktop

Desktop computers are personal computers (PCs) designed for use by an individual at a fixed location. IBM was the first computer to introduce and popularize use of desktops. A desktop unit typically has a CPU (Central Processing Unit), monitor, keyboard and mouse. Introduction of desktops popularized use of computers among common people as it was compact and affordable.

Riding on the wave of desktop’s popularity many software and hardware devices were developed specially for the home or office user. The foremost design consideration here was user friendliness.

Laptop

Despite its huge popularity, desktops gave way to a more compact and portable personal computer called laptop in 2000s. Laptops are also called notebook computers or simply notebooks. Laptops run using batteries and connect to networks using Wi-Fi (Wireless Fidelity) chips. They also have chips for energy efficiency so that they can conserve power whenever possible and have a longer life.

Modern laptops have enough processing power and storage capacity to be used for all office work, website designing, software development and even audio/video editing.

Tablet

After laptops computers were further miniaturized to develop machines that have processing power of a desktop but are small enough to be held in one’s palm. Tablets have touch sensitive screen of typically 5 to 10 inches where one finger is used to touch icons and invoke applications.

Keyboard is also displayed virtually whenever required and used with touch strokes. Applications that run on tablets are called apps. They use operating systems by Microsoft (Windows 8 and later versions) or Google (Android). Apple computers have developed their own tablet called iPad which uses a proprietary OS called iOS.

Server

Servers are computers with high processing speeds that provide one or more services to other systems on the network. They may or may not have screens attached to them. A group of computers or digital devices connected together to share resources is called a network.

Servers have high processing powers and can handle multiple requests simultaneously. Most commonly found servers on networks include 

•  File or storage server
•  Game server
•  Application server
•  Database server
•  Mail server
•  Print server

Mainframe

Mainframes are computers used by organizations like banks, airlines and railways to handle millions and trillions of online transactions per second. Important features of mainframes are 

•  Big in size
•  Hundreds times Faster than servers, typically hundred megabytes per second
•  Very expensive
•  Use proprietary OS provided by the manufacturers
•  In-built hardware, software and firmware security features

Supercomputer

Supercomputers are the fastest computers on Earth. They are used for carrying out complex, fast and time intensive calculations for scientific and engineering applications. Supercomputer speed or performance is measured in teraflops, i.e. 1012 floating point operations per second.

Chinese supercomputer Sunway TaihuLight is the world’s fastest supercomputer with a rating of 93 petaflops per second, i.e. 93 quadrillion floating point operations per second.

Most common uses of supercomputers include 

•  Molecular mapping and research
•  Weather forecasting
•  Environmental research
•  Oil and gas exploration

INTRODUCTION TO COMPUTER

Being a modern-day kid you must have used, seen, or read about computers. This is because they are an integral part of our everyday existence. Be it school, banks, shops, railway stations, hospital or your own home, computers are present everywhere, making our work easier and faster for us. As they are such integral parts of our lives, we must know what they are and how they function. Let us start with defining the term computer formally.

The literal meaning of computer is a device that can calculate. However, modern computers can do a lot more than calculate. Computer is an electronic device that receives input, stores or processes the input as per user instructions and provides output in desired format.

Input-Process-Output Model

•  Computer input is called data and the output obtained after processing it, based on user’s instructions is called information. Raw facts and figures which can be processed using arithmetic and logical operations to obtain information are called data.

The processes that can be applied to data are of two types

•  Arithmetic operations: Examples include calculations like addition, subtraction, differentials, square root, etc.

•  Logical operations: Examples include comparison operations like greater than, less than, equal to, opposite, etc.

The corresponding figure for an actual computer looks something like this

The basic parts of a computer are as follows

•  Input Unit: Devices like keyboard and mouse that are used to input data and instructions to the computer are called input unit.

•  Output Unit: Devices like printer and visual display unit that are used to provide information to the user in desired format are called output unit.

•  Control Unit: As the name suggests, this unit controls all the functions of the computer. All devices or parts of computer interact through the control unit.

•  Arithmetic Logic Unit: This is the brain of the computer where all arithmetic operations and logical operations take place.

•  Memory: All input data, instructions and data interim to the processes are stored in the memory. Memory is of two types primary memory and secondary memory. Primary memory resides within the CPU whereas secondary memory is external to it.

Control unit, arithmetic logic unit and memory are together called the central processing unit or CPU. Computer devices like keyboard, mouse, printer, etc. that we can see and touch are the hardware components of a computer. The set of instructions or programs that make the computer function using these hardware parts are called software. We cannot see or touch software. Both hardware and software are necessary for working of a computer.

Characteristics of Computer

To understand why computers are such an important part of our lives, let us look at some of its characteristics

•  Speed: Typically, a computer can carry out 3-4 million instructions per second.

•  Accuracy: Computers exhibit a very high degree of accuracy. Errors that may occur are usually due to inaccurate data, wrong instructions or bug in chips all human errors.

•  Reliability: Computers can carry out same type of work repeatedly without throwing up errors due to tiredness or boredom, which are very common among humans.

•  Versatility: Computers can carry out a wide range of work from data entry and ticket booking to complex mathematical calculations and continuous astronomical observations. If you can input the necessary data with correct instructions, computer will do the processing.

•  Storage Capacity: Computers can store a very large amount of data at a fraction of cost of traditional storage of files. Also, data is safe from normal wear and tear associated with paper.

Advantages of Using Computer

Now that we know the characteristics of computers, we can see the advantages that computers offer−

•  Computers can do the same task repetitively with the same accuracy.

•  Computers do not get tired or bored.

•  Computers can take up routine tasks while releasing human resource for more intelligent functions.

Disadvantages of Using Computer

Despite so many advantages, computers have some disadvantages of their own

•  Computers have no intelligence; they follow the instructions blindly without considering the outcome.

•  Regular electric supply is necessary to make computers work, which could prove difficult everywhere especially in developing nations.

Booting

Starting a computer or a computer-embedded device is called booting. Booting takes place in two steps

•  Switching on power supply
•  Loading operating system into computer’s main memory
•  Keeping all applications in a state of readiness in case needed by the user

The first program or set of instructions that run when the computer is switched on is called BIOS or Basic Input Output System. BIOS is a firmware, i.e. a piece of software permanently programmed into the hardware.

If a system is already running but needs to be restarted, it is called rebooting. Rebooting may be required if a software or hardware has been installed or system is unusually slow.

There are two types of booting

•  Cold Booting: When the system is started by switching on the power supply it is called cold booting. The next step in cold booting is loading of BIOS.

•  Warm Booting: When the system is already running and needs to be restarted or rebooted, it is called warm booting. Warm booting is faster than cold booting because BIOS is not reloade.

AntiVirus

Antivirus software is designed to find known viruses and oftentimes other malware such as Ransomware, Trojan Horses, worms, spyware, adware, etc., that can have a detrimental impact to the user or device.

Antivirus programs provide a way to protect against known threats. The effectiveness of an antivirus program is heavily dependent on how often it is updated. Therefore, it is important to have the antivirus program scheduled to update daily.  Most antivirus programs rely on a library or database of known viruses that they use to compare with programs on a user’s device. If a match is found, the malicious program will either be deleted or placed into a quarantine area from which a user can decide to restore or delete the program manually.

One limitation of traditional antivirus programs is that they only provide protection against known threats. Therefore, if someone cooks up new malicious code, an antivirus program may fail to detect it when a scan is done. Users should not consider an antivirus program to be universal protection against all viruses and malware. Instead, users should consider an antivirus program to be one part of a comprehensive online security hygiene regimen. Security experts refer to this aspect of information security as Endpoint Protection.

There are some antivirus manufacturers that are incorporating predictive analysis and artificial intelligence into their antivirus software to be able to detect new malicious programs. They focus on detecting malicious software based on what it does, as opposed to whether it exists in a library or dictionary. While we cannot recommend one antivirus program over another, we encourage users to do independent research to find which antivirus program will work best for them.

Have you ever downloaded a file, opened it and been a victim of excessive pop-ups thereafter? Chances are the file installed an adware program on your computer when you opened it. An antivirus program could have stopped this if:

1. The malicious software was known to the antivirus company. 
2. The antivirus program was up to date.

This example showcases the strengths and weaknesses of antivirus programs. They are very efficient at what they do, but they will only protect against malicious programs that are known, and only if kept updated. The good news is, there are countless types of malicious software that antivirus companies know about, and they are becoming more and more efficient at discovering new varieties every day.

We recommend that users take several steps to avoid infection by a virus or malware.

1. The first step a user must make is to decide which antivirus program will be best for them. There are many free and paid versions of antivirus programs available. We encourage users to examine trusted sources or reviews of different antivirus programs.
2. When installing the antivirus program, it is best to set up scheduled updates. The antivirus program will usually prompt you during the setup process to schedule a certain time or frequency for updates. We recommend a daily update at a time when your computer will be on but not in use. It is also a good idea to have a thorough first scan to remove any viruses or malware that may already be on the device.
3. Ensure scans are performed at regular intervals. We recommend daily scans at a time when you are not using the device.
4. If you are using a paid antivirus program, it is important to ensure the subscription is renewed to avoid gaps in coverage.
5. Finally, be careful what sites you visit. All an attacker needs is for you to land on their dirty page. Visit only reputable sites.

With an antivirus program configured with regular updates and scans, users should feel safe from known threats. Antivirus programs are a key part to a user’s total cybersecurity hygiene practice.

Advantages

1. Virus Protection

The main role of an antivirus program is to stand against viruses and other forms of malwares. The viruses will not only cause damages to your data, it can degrade the overall system performance. All of them can happen without your knowledge. The antivirus software installed on your computer detects and removes these malwares before they cause any harms to your computer.


2. Spyware Protection

Spyware as the name suggests is a kind of malware that spies on your computer stealing all the confidential informations. These details also include credit card details, passwords and other financial datas. This ultimately leads to identity theft. The antivirus software has the capability to prevent these kinds of spyware attacks.


3. Web Protection

While surfing the internet, users can come across various other forms of threats. In an untrustworthy sites, cyber attackers can gather your credit card and bank account details. One of the way to overcome this is by using an antivirus software. Using antivirus program you can protect your valuable informations while surfing the web.


4. Spam Protection

Viruses can also enter your computer through means of spam emails and ads. These emails and ads can show up many times even if your have no interest in it. Once the virus finds the way to sneak into your PC it cause irreversible damages. An Antivirus works by the way of blocking these spam emails and ads.


5. Firewall Feature

Most antivirus programs include a firewall feature in them. Antivirus program with firewall feature ensures 2 way protection to your PC. This means that whatever the information that is sent or received will be double checked here. Therefore, no hackers can dig any personal informations from your system.


6. Cost Effective

Even thought there are many premium versions of antivirus programs for a monthly/yearly subscription fee, there are some antivirus programs those are completely free of charge. These kinds of antivirus programs offer almost the same level of protection provided by the subscription based. Even if you choose to afford a premium version, they are relatively inexpensive.

Disadvantages

1. System Slowdown

Using an antivirus program means that a lot of resources from the memory and the hard drive is being used. As a result it can drastically slowdown overall speed of the computer. Moreover, the process of scanning can also cause lags in the network.


2. No Complete Protection

If you are using a free antivirus program, there is no guarantee that it will provide you the complete protection. Most free antivirus programs out there only offer a basic level of protection. Moreover they are capable of identifying only certain types of threats. In order for acquiring complete level of protection, you have to use a firewall as well.


3. Security Holes

When security holes are present inside the operating system or the networking software, it will provide a chance for the virus to bypass the antivirus software. Unless the user takes actions to keep it update, the antivirus software won't be effective.


4. Limited Detection Techniques

For identifying a potential threat, there are always more than one method available. However in the case of antivirus program, it mostly executes the method of virus scanning. Basically what happens in the process of scanning is, it will try to search for the virus code patterns. Sometimes the antivirus programs can give you false alarms if the scanning matches with the normal file. Furthermore, if there are any new types of viruses the antivirus program will fail to identify it completely. That is the reason why antivirus software needs to be updated often.


5. Frequent Advertisements

Apart from premium versions of antivirus programs, through some means the free antivirus softwares needs to generate an income. Advertising is one of the ways to achieve them. Many at times these advertisements degrade user experience by showing up every time.


6. No Customer Support

Another drawback of a free antivirus program is that it lacks on the side of customer support. Unless you pay for the premium version, there won't be any customer support given to you. In the event of any problem, the only way to overcome is through forums and knowledge bases.

 

 

What is computer security?

Computer security basically is the protection of computer systems and information from harm, theft, and unauthorized use. It is the process of preventing and detecting unauthorized use of your computer system.

There are various types of computer security which is widely used to protect the valuable information of an organization.

What is Computer Security and its types?

One way to ascertain the similarities and differences among Computer Security is by asking what is being secured. For example,

• Information Security is securing information from unauthorized access, modification & deletion
• Application Security is securing an application by building security features to prevent from Cyber Threats such as SQL injection, DoS attacks, data breaches and etc.
• Computer Security means securing a standalone machine by keeping it updated and patched
• Network Security is by securing both the software and hardware technologies
• Cybersecurity is defined as protecting computer systems, which communicate over the computer networks

It’s important to understand the distinction between these words, though there isn’t necessarily a clear consensus on the meanings and the degree to which they overlap or are interchangeable.

 

So, Computer security can be defined as controls that are put in place to provide confidentiality, integrity, and availability for all components of computer systems. Let’s elaborate the definition.

Components of computer system

The components of a computer system that needs to be protected are:

• Hardware, the physical part of the computer, like the system memory and disk drive
• Firmware, permanent software that is etched into a hardware device’s nonvolatile memory and is mostly invisible to the user
• Software, the programming that offers services, like operating system, word processor, internet browser to the user 

Computer security threats

Computer security threats are possible dangers that can possibly hamper the normal functioning of your computer. In the present age, cyber threats are constantly increasing as the world is going digital. The most harmful types of computer security are:

Viruses

A computer virus is a malicious program which is loaded into the user’s computer without user’s knowledge. It replicates itself and infects the files and programs on the user’s PC. The ultimate goal of a virus is to ensure that the victim’s computer will never be able to operate properly or even at all. 

Computer Worm

A computer worm is a software program that can copy itself from one computer to another, without human interaction. The potential risk here is that it will use up your computer hard disk space because a worm can replicate in greate volume and with great speed.

Phishing

Disguising as a trustworthy person or business, phishers attempt to steal sensitive financial or personal information through fraudulent email or instant messages. Phishing in unfortunately very easy to execute. You are deluded into thinking it’s the legitimate mail and you may enter your personal information.

Botnet

A botnet is a group of computers connected to the internet, that have been compromised by a hacker using a computer virus. An individual computer is called ‘zombie computer’. The result of this threat is the victim’s computer, which is the bot will be used for malicious activities and for a larger scale attack like DDoS.

Rootkit

A rootkit is a computer program designed to provide continued privileged access to a computer while actively hiding its presence. Once a rootkit has been installed, the controller of the rootkit will be able to remotely execute files and change system configurations on the host machine.

Keylogger

Also known as a keystroke logger, keyloggers can track the real-time activity of a user on his computer. It keeps a record of all the keystrokes made by user keyboard. Keylogger is also a very powerful threat to steal people’s login credential such as username and password.

Why is Computer Security Important?

In this digital era, we all want to keep our computers and our personal information secure and hence computer security is important to keep our personal information protected. It is also important to maintain our computer security and its overall health by preventing viruses and malware which would impact on the system performance.

Computer Security Practices

Computer security threats are becoming relentlessly inventive these days. There is much need for one to arm oneself with information and resources to safeguard against these complex and growing computer security threats and stay safe online. Some preventive steps you can take include:

• Secure your computer physically by:
  • Installing reliable, reputable security and anti-virus software
  • Activating your firewall, because a firewall acts as a security guard between the internet and your local area network 
• Stay up-to-date on the latest software and news surrounding your devices and perform software updates as soon as they become available
• Avoid clicking on email attachments unless you know the source 
• Change passwords regularly, using a unique combination of numbers, letters and case types
• Use the internet with caution and ignore pop-ups, drive-by downloads while surfing
• Taking the time to research the basic aspects of computer security and educate yourself on evolving cyber-threats
• Perform daily full system scans and create a periodic system backup schedule to ensure your data is retrievable should something happen to your computer.