Your answer to this question shows your knowledge of the two main software development paradigms. Here are the differences between the two:

• Functional programming relies on immutable objects and avoids mutating states. Object-oriented programming depends on state mutation and the in-place modification of objects.
• The main concept in functional programming is the function. In object-oriented programming, it's the class.

An abstract class is a class that contains abstract methods. These methods have declarations but no implementations. Instead, they're implemented by sub-classes of the abstract class, which makes them more flexible and easier to customize.

Verification:

Verification is a term that refers to the set of activities which ensure that software implements a specific function.

Validation:

It refers to the set of activities which ensure that software that has been built according to the need of clients.

Software Testing can be majorly classified into two categories:

• Black Box Testing is a software testing method in which the internal structure/ design/ implementation of the item being tested is not known to the tester.
• White Box Testing is a software testing method in which the internal structure/ design/ implementation of the item being tested is known to the tester.

Functional requirements are the features that a developed software product is expected to perform. For example, adding a payment option at an eCommerce website will be a functional requirement. Non-functional requirements measure the usability of the application such as User Interface look and feel, Security, Performance, Interoperability, Reliability, etc.

Every developer has their views when it comes to the programming language choices. Though, one should prefer high-level languages because they are dynamic. Like C and C++ languages.

Software requirements are a functional description of a proposed software system. It is assumed to be the description of the target system, its functionalities, and features.

It is a measure to find out how practical and beneficial the software project development will prove to the organization. The software analyzer conducts a study to know the economic, technical and operational feasibility of the project.

1. Economic: It includes the cost of training, cost of additional and tools and overall estimation of costs and benefits of the project.
2. Technical: It evaluate technical aspect. Is it possible to develop this system? Assessing the suitability of machine(s) and OS on which software will execute, knowledge of the software development and tools available for this project.
3. Operational: Here the analyst need to assess that the organization will able to adjust smoothly to the changes done as per the demand for the project. Is the problem worth solving at the estimated cost?

After, studying all this the final feasibility report is created.

The Feasibility Study in Software Engineering is a study to assess the adequacy of proposed projects and systems. A feasibility study is a measure of a software product on how product development can benefit an organization from a validity analysis or practical point of view. Feasibility studies are conducted for multiple purposes to analyze the correctness of a software product in terms of development, porting, the contribution of an organization’s projects, and so on.

Cohesion indicates the relative functional capacity of the module. Aggregation modules need to interact less with other sections of other parts of the program to perform a single task. It can be said that only one coagulation module (ideally) needs to be run. Cohesion is a measurement of the functional strength of a module. A module with high cohesion and low coupling is functionally independent of other modules. Here, functional independence means that a cohesive module performs a single operation or function. The coupling means the overall association between the modules.

Coupling relies on the information delivered through the interface with the complexity of the interface between the modules in which the reference to the section or module was created. High coupling support Low coupling modules assume that there are virtually no other modules. It is exceptionally relevant when both modules exchange a lot of information. The level of coupling between two modules depends on the complexity of the interface.

Cohesion is a measure that defines the intra-dependability among the elements of the module.

ome of the most important software analysis and designing tools are:

• Data Flow Diagrams
• Structured Charts
• Structured English
• Data Dictionary
• Hierarchical Input Process Output diagrams
• Entity Relationship Diagrams and Decision tables

Structured English is native English language. It is used to write the structure of a program module. It uses programming language keywords. On the other hand, Pseudo Code is more like to the programming language without syntax of any specific language.

Quality Assurance checks if proper process is followed while developing the software while Quality Control deals with maintaining the quality of software product.

A process is instance of the computer program.In a single program it is possible to have one or more threads.

>

Computer aided software engineering (CASE) is the implementation of computer facilitated tools and methods in software development. CASE is used to ensure a high-quality and defect-free software. CASE ensures a check-pointed and disciplined approach and helps designers, developers, testers, managers and others to see the project milestones during development. 

• Requirement Analysis Tool
• Structure Analysis Tool
• Software Design Tool
• Code Generation Tool
• Test Case Generation Tool
• Document Production Tool
• Reverse Engineering Tool

Various tools are incorporated in CASE and are called CASE tools, which are used to support different stages and milestones in a software development life cycle. 

Types of CASE Tools: 

• Diagramming Tools: 
  It helps in diagrammatic and graphical representations of the data and system processes. It represents system elements, control flow and data flow among different software components and system structure in a pictorial form. For example, Flow Chart Maker tool for making state-of-the-art flowcharts. 
• Computer Display and Report Generators: It helps in understanding the data requirements and the relationships involved. 
• Analysis Tools: It focuses on inconsistent, incorrect specifications involved in the diagram and data flow. It helps in collecting requirements, automatically check for any irregularity, imprecision in the diagrams, data redundancies or erroneous omissions. For example, 
  • Accept 360, Accompa, CaseComplete for requirement analysis. 
  • Visible Analyst for total analysis. 
• Central Repository: It provides the single point of storage for data diagrams, reports and documents related to project management.
• Documentation Generators:  It helps in generating user and technical documentation as per standards. It creates documents for technical users and end users. For example, Doxygen, DrExplain, Adobe RoboHelp for documentation. 
• Code Generators: It aids in the auto generation of code, including definitions, with the help of the designs, documents and diagrams. 

Advantages of the CASE approach:

• As special emphasis is placed on redesign as well as testing, the servicing cost of a product over its expected lifetime is considerably reduced. 
• The overall quality of the product is improved as an organized approach is undertaken during the process of development. 
• Chances to meet real-world requirements are more likely and easier with a computer-aided software engineering approach. 
• CASE indirectly provides an organization with a competitive advantage by helping ensure the development of high-quality products. 

Disadvantages of the CASE approach: 

• Learning Curve: In most cases, programmers productivity may fall in the initial phase of implementation , because user need time to learn the technology. Many consultants offer training and on-site services that can be important to accelerate the learning curve and to the development and use of the CASE tools.
• Cost: Using case tool is a very costly. Mostly firms engaged in software development on a small scale do not invest in CASE tools because they think that the benefit of CASE are justifiable only in the development of large systems.
• Tool Mix: It is important to build an appropriate selection tool mix to urge cost advantage CASE integration and data integration across all platforms is extremely important. 

There are six major characteristics of software

• Functionality: The things that software is intended to do are called functionality. For example, a calculator's functionality is to perform mathematical operations.
• Efficiency: It is the ability of the software to use the provided resources in the best way possible. Increasing the efficiency of software increases resource utilization and reduces cost.
• Reliability:Reliability is the probability of failure-free operational software in an environment. It is an important characteristic of software.
• Usability:It refers to the user’s experience while using the software. Usability determines the satisfaction of the user.
• Maintainability: The ease with which you can repair, improve, and comprehend software code is referred to as maintainability. After the customer receives the product, a phase in the software development cycle called software maintenance begins.
• Portability: It refers to the ease with which the software product can be transferred from one environment to another.

Apart from the above-mentioned characteristics, the software also has the following characteristics:

• Software is engineered, it is not developed or manufactured like hardware. Development is an aspect of the hardware manufacturing process. Manufacturing does not exist in the case of software.
• The software doesn't wear out.
• The software is custom-built.