Software Engineering is the process of developing a software product in a well-defined systematic approach software engineering is the process of analyzing user needs and then designing, constructing, and testing end-user applications that will satisfy these needs through the use of software programming languages.
The software should be produced at a reasonable cost, in a reasonable time, and should be of good quality. these three parameters often drive and define a software project.
- Cost: As the main cost of producing software is the manpower employed, the cost of developing software is generally measured in terms of person-months of effort spent in development. The productivity in the software industry for writing fresh code generally ranges from a few hundred to about 1000 + LOC per person per month.
- Schedule: The schedule is another important factor in many projects. Business trends are dictating that the time to market a product should be reduced; that is, the cycle time from concept to delivery should be small. this means that software needs to be developed faster and within the specified time.
- Quality: Quality is one of the main mantras, and business strategies are designed around it. Developing high-quality software is another fundamental goal of software engineering.
- Attributes of Software
The international standard on software product quality suggests that software quality comprises six main attributes:
- Reliability: The capability to provide failure-free service.
- Functionality: The capability to provide functions that meet stated and implied needs when the software is used.
- Usability: The capability to be understood, learned, and used.
- Efficiency: The capability to provide appropriate performance relative to the amount of resources used.
- Maintainability: the capability to be modified for purposes of making corrections, improvements, or adaptations.
- Portability: The capability to be adapted for different specified environments without applying actions or means other than those provided for this purpose in the product.
Classification of Software
The software can be classified based on various criteria, including:
- Purpose: Software can be classified as system software (e.g. operating systems, device drivers) or application software (e.g. word processors, games).
- Platform: Software can be classified as native software (designed for a specific operating system) or cross-platform software (designed to run on multiple operating systems).
- Deployment: Software can be classified as installed software (installed on the user’s device) or cloud-based software (hosted on remote servers and accessed via the internet).
- License: Software can be classified as proprietary software (owned by a single entity) or open-source software (available for free with the source code accessible to the public).
- Development Model: Software can be classified as traditional software (developed using a waterfall model) or agile software (developed using an iterative and adaptive approach).
- Size: Software can be classified as small-scale software (designed for a single user or small group) or enterprise software (designed for large organizations).
- User Interface: Software can be classified as Graphical User Interface (GUI) software or Command-Line Interface (CLI) software.
These classifications are important for understanding the characteristics and limitations of different types of software, and for selecting the best software for a particular need.
Types of Software
The software is used extensively in several domains including hospitals, banks, schools, defense, finance, stock markets, and so on. It can be categorized into different types:
- Based on Application
- Based on Copyright
Based on Application
The software can be classified on the basis of the application. These are to be done on this basis.
1. System Software
System Software is necessary to manage computer resources and support the execution of application programs. Software like operating systems, compilers, editors and drivers, etc., come under this category. A computer cannot function without the presence of these. Operating systems are needed to link the machine-dependent needs of a program with the capabilities of the machine on which it runs. Compilers translate programs from high-level language to machine language.
2. Application Software
Application software is designed to fulfill the user’s requirement by interacting with the user directly. It could be classified into two major categories:- generic or customized. Generic Software is software that is open to all and behaves the same for all of its users. Its function is limited and not customized as per the user’s changing requirements. However, on the other hand, Customized software is the software products designed per the client’s requirement, and are not available for all.
3. Networking and Web Applications Software
Networking Software provides the required support necessary for computers to interact with each other and with data storage facilities. Networking software is also used when software is running on a network of computers (such as the World Wide Web). It includes all network management software, server software, security and encryption software, and software to develop web-based applications like HTML, PHP, XML, etc.
4. Embedded Software
This type of software is embedded into the hardware normally in the Read-Only Memory (ROM) as a part of a large system and is used to support certain functionality under the control conditions. Examples are software used in instrumentation and control applications like washing machines, satellites, microwaves, etc.
5. Reservation Software
A Reservation system is primarily used to store and retrieve information and perform transactions related to air travel, car rental, hotels, or other activities. They also provide access to bus and railway reservations, although these are not always integrated with the main system. These are also used to relay computerized information for users in the hotel industry, making a reservation and ensuring that the hotel is not overbooked.
6. Business Software
This category of software is used to support business applications and is the most widely used category of software. Examples are software for inventory management, accounts, banking, hospitals, schools, stock markets, etc.
7. Entertainment Software
Education and Entertainment software provides a powerful tool for educational agencies, especially those that deal with educating young children. There is a wide range of entertainment software such as computer games, educational games, translation software, mapping software, etc.
8. Artificial Intelligence Software
Software like expert systems, decision support systems, pattern recognition software, artificial neural networks, etc. come under this category. They involve complex problems which are not affected by complex computations using non-numerical algorithms.
9. Scientific Software
Scientific and engineering software satisfies the needs of a scientific or engineering user to perform enterprise-specific tasks. Such software is written for specific applications using principles, techniques, and formulae particular to that field. Examples are software like MATLAB, AUTOCAD, PSPICE, ORCAD, etc.
10. Utility Software
The programs coming under this category perform specific tasks and are different from other software in terms of size, cost, and complexity. Examples are anti-virus software, voice recognition software, compression programs, etc.
11. Document Management Software
Document Management Software is used to track, manage, and store documents to reduce the paperwork. Such systems are capable of keeping a record of the various versions created and modified by different users (history tracking). They commonly provide storage, versioning, metadata, security, as well as indexing and retrieval capabilities.
Based on Copyright
Classification of Software can be done based on copyright. These are stated as follows:
1. Commercial Software
It represents the majority of software that we purchase from software companies, commercial computer stores, etc. In this case, when a user buys software, they acquire a license key to use it. Users are not allowed to make copies of the software. The company owns the copyright of the program.
2. Shareware Software
Shareware software is also covered under copyright but the purchasers are allowed to make and distribute copies with the condition that after testing the software, if the purchaser adopts it for use, then they must pay for it. In both of the above types of software, changes to the software are not allowed.
3. Freeware Software
In general, according to freeware software licenses, copies of the software can be made both for archival and distribution purposes but here, distribution cannot be for making a profit. Derivative works and modifications to the software are allowed and encouraged. Decompiling of the program code is also allowed without the explicit permission of the copyright holder.
4. Public Domain Software
In the case of public domain software, the original copyright holder explicitly relinquishes all rights to the software. Hence software copies can be made both for archival and distribution purposes with no restrictions on distribution. Modifications to the software and reverse engineering are also allowed.
Frequently Asked Questions
1. How is System Software classified?
Answer:
System Software is classified on the basis of how the tasks are to be performed and how the software system interacts.
2. What are the five functions of the Software?
Answer:
Software is the program that is required to work on the input, processing, output, storage and control.
