Open Source

Open-source software(OSS) is computer software that is available in source code form for which the source code and certain other rights normally reserved for copyright holders are provided under a software license that permits the users to study, change and improve the software. Open source licenses often meet the requirements of the Open Source Definition. Some open source software is available within the public domain. Open source software is very often developed in a public, collaboratively manner. Open-source
software is the most prominent example of open-source development and often compared to user-generated content. The term open-source software originated as part of a marketing campaign for free software. A report by Standish Group states that adoption of open-source software models has resulted in savings of about $60 billion per year to consumers.

Software Development

Software development is the act of working to produce/create software. This software could be produced for a variety of purposes - the three most common purposes are to meet specific needs of a specific client/business, to meet a perceived need of some set of potential users (the case with commercial and open source software), or for personal use (e.g. a scientist may write software to automate a mundane task).

The term software development is often used to refer to the activity of computer programming, which is the process of writing and maintaining the source code, whereas the broader sense of the term includes all that is involved between the conception of the desired software through to the final manifestation of the software. Therefore, software development may include research, new development, modification, reuse, re-engineering, maintenance, or any other activities that result in software products. For larger software systems, usually developed by a team of people, some form of process is typically followed to guide the stages of production of the software.

Especially the first phase in the software development process may involve many departments, including marketing, engineering, research and development and general management.

Software Engineering

Software engineering is a profession and field of study dedicated to designing, implementing, and modifying software so that it is of higher quality, more affordable, maintainable, and faster to build. The term software engineering first appeared in the 1968 NATO Software Engineering Conference, and was meant to provoke thought regarding the perceived "software crisis" at the time. Since the field is still relatively young compared to its sister fields of engineering, there is still much debate around what software engineering actually is, and if it conforms to the classical definition of engineering. Some people argue that development of computer software is more art than science , and that attempting to impose engineering disciplines over a type of art is an exercise in futility because what represents good practice in the creation of software is not even defined. Others, such as Steve McConnell, argue that engineering's blend of art and science to achieve practical ends provides a useful model for software development. The IEEE Computer Society 's Software Engineering Body of Knowledge "software engineering" as the application of a systematic, disciplined, quantifiable approach to the development, operation, and maintenance of software, and the study of these approaches; that is, the application of engineering to software.

Computer Virus

A computer virus is a computer program that can copy itself and infect a computer. The term "virus" is also commonly but erroneously used to refer to other types of malware, adware, and spyware programs that do not have the reproductive ability. A true virus can only spread from one computer to another (in some form of executable code) when its host is taken to the target computer; for instance because a user sent it over a network or the Internet, or carried it on a removable medium such as a floppy disk, CD, DVD, or USB drive. Viruses can increase their chances of spreading to other computers by infecting files on a network file system or a file system that is accessed by another computer.

As stated above, the term "computer virus" is sometimes used as a catch-all phrase to include all types of malware, adware, and spyware programs that do not have the reproductive ability. Malware includes computer viruses, worms, trojans, most rootkits, spyware, dishonest adware, crimeware, and other malicious and unwanted software, including true viruses. Viruses are sometimes confused with computer worms and Trojan horses, which are technically different. A worm can exploit security vulnerabilities to spread itself automatically to other computers through networks, while a Trojan is a program that appears harmless but hides malicious functions. Worms and Trojans, like viruses, may harm a computer system's data or performance. Some viruses and other malware have symptoms noticeable to the computer user, but many are surreptitious and go unnoticed.

Application Software

Application software, also known as software application, application or app, is computer software designed to help the user to perform singular or multiple related specific tasks. Typical examples are word processors, spreadsheets, media players and database applications.
Application software should be contrasted with system software (infrastructure) or middleware (computer services/ processes integrators), which is involved in integrating a computer's various capabilities, but typically does not directly apply them in the performance of tasks that benefit the user. A simple, if imperfect analogy in the world of hardware would be the relationship of an electric light bulb (an application) to an electric power generation plant (a system). The power plant merely generates electricity, not itself of any real use until harnessed to an application like the electric light that performs a service that benefits the user.

Computer Security

The term computer security is used frequently, but the content of a computer is vulnerable to few risks unless the computer is connected to other computers on a network. As the use of computer networks, especially the Internet, has become pervasive, the concept of computer security has expanded to denote issues pertaining to the networked use of computers and their resources.

Computer Security

Computer security is a branch of computer technology known as information security as applied to computers and networks. The objective of computer security includes protection of information and property from theft, corruption, or natural disaster, while allowing the information and property to remain accessible and productive to its intended users. The term computer system security means the collective processes and mechanisms by which sensitive and valuable information and services are protected from publication, tampering or collapse by unauthorized activities or untrustworthy individuals and unplanned events respectively. The strategies and methodologies of computer security often differ from most other computer technologies because of its somewhat eluding objective of preventing unwanted computer behavior instead of enabling wanted computer behavior.

Introduction of Computer

Computer is an electronic machine that can receive input, store and manipulate data, and can provide output in a useful format according to the requirement of its user. It has become one of the most important and useful invention in the history if the world. As the computer was invented it changed the entire world by the mysterious and wonderful abilities it can do. The whole world is fond of using computer in the present days and can't even stay without using it for a second. It can do lots of amazing and interesting works due to which everyone becomes surprised and be fond of computer.

We can play games, watch movies, videos, different channels, listen musics, chat with different people worldwide.
Computer itself cannot do anything to do work, but it requires a user to give instructions to it to do some specific task.

Now a days computer are being used in different sectors, areas such as education, hospitals, military, scientific researches, online banking, shopping, job, etc.