A Complete Guide on Software Testing
Software Testing is a process to evaluate the functionality of software with an intent to find and resolve bugs.
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As every aspect of our life is transforming into digital versions, we find ourselves more intrigued by their underlying software’s functioning. Software is controlling everything that is digitized.
But how can we ensure that the software involved in controlling so many aspects of our lives are efficient and not full of defects? This is where Software Testing steps in.
In this detailed guide, we will cover the following topics about Software Testing.
- What is Software Testing?
- Why is Software Testing important?
- What are the types of Software Testing?
- What are the methods of Software Testing?
- What are the approaches to Software Testing?
- What are the levels of Software Testing?
- What are the different testing process models?
- What are the various tools for Software Testing?
- What are the Software Testing deliverables?
- What are the Principles of Software Testing?
- What qualities should you look for in your software testing team?
Let’s get started by understanding the meaning of software testing.
1. What Is Software Testing?
As defined by the ANSI/IEEE 1059 standard,
Testing is the process of analyzing a software item to detect the differences between existing and required conditions (that is, defects/errors/bugs) and to evaluate the features of the software item.
Software Testing is a way to ensure that the end product matches the expected standards. The aim of software testing is:
- To evaluate functionality.
- To identify bugs and defects.
- To identify gaps between existing and expected conditions.
Also, Software Testing provides an impartial and independent view of the software, which helps understand its pros and cons.
2. Why Is Software Testing Important?
It is essential to ensure the superior functioning of the software. Many losses can be avoided by testing software before implementing it.
Software Testing offers numerous advantages, making it a crucial step before delivering the final product to the customer.
Advantages of Software Testing
- Saves Money
- There are many ways you can make the process of software development a little cost-effective. One way is to test the software properly. You can save a lot of money by testing software before implementing it. Executing faulty software will cost you numerous investments, users, and clients. Also, testing ensures that your software does not need continuous fixing – thus saving money in the long run.
- Software testing aims to remove bugs and defects in your software to ensure smooth functioning. Hence, you can guarantee high-quality software to your clients. Delivering good quality software also plays a significant role in building a brand image. High-quality software attracts more customers and higher payments.
- User Experience
- User Experience plays an essential role in deciding the successful launch of the software. A user will only use software continuously if it is basic and straightforward. If the user experience is terrible, it will be complicated or challenging to use the software.
The software needs to be simple, direct, easy to use and ensure a good user experience. It is essential to test software rigorously for this purpose.
Flawless user experience leads to recommendations and a boost in your business.
- Brings Profits
- Software testing plays an essential role in bringing profits. It heightens the Return of Investment by ensuring good quality.
Rigorous Software Testing leads to high-quality and efficient software, resulting in good user experience, client satisfaction, and good word-of-mouth. It will help you to retain old clients as well as gain new ones. Hence, it leads to profits. Also, since software testing enables you to remove as many bugs as possible in the early stages of development, long-run investments in debugging reduce.
- Business Optimization
Business optimization implies happy users, client retention, low servicing costs, increased profits, better quality, and superior brand image. All this depends on the quality of the software you offer to your users, which can be ensured only with careful and continuous Software Testing.
Faulty software can also lead to disturbed communication within your company, causing unnecessary problems and inefficiency. The implications of faulty software can be avoided with the help of Software Testing.
3. What Are the Types of Software Testing?
Software Testing is of two types:
Testing software only by human intervention is known as manual testing. Verification of existing conditions with requirements is done. Manual testing may include detailed step-by-step test cases for testing periods.
Some advantages of Manual Testing are:
Manual Testing can save you the costs of using automatic tools to test software.
- Nothing can beat the human eye
There are many instances when the human eye catches something which goes unseen by an automated tool. If something looks “off,” it can immediately be rectified by the tester.
- User Experience modification –
You cannot rely entirely on an automated tool to provide you with the best user experience. Some things, like visual or design bugs, can be identified more effectively by the human eye.
- Flexibility – With manual testing, the advantage of flexibly rectifying bugs is added.
Testing software by using automation tools is known as automation testing. There are various tools accessible that can assist you in automatically testing your software, which will be discussed later in this article.
Some advantages of Automation Testing are:
- Test execution can be scheduled
- With automation testing, you can schedule the software testing anytime from anywhere. It provides this flexibility as you don’t have to be physically present for the testing. You have automated tools to assist you.
- Regression testing is easy
- Regression testing refers to running functional and non-functional tests repeatedly to ensure the smooth functioning of the software after a change has been made. It is the pain spot for every software tester as it is tedious and time-consuming. Automation testing eases this process as you can schedule and conduct the regression test to be performed automatically at any time.
- It enables you to reuse your test scripts.
- Saves time
- Automation testing increases the speed as you don’t have to overlook it manually. It frees you from spending a lot of time on test scripts and repeated testing, hence increasing your efficiency and offering you a chance to work on other aspects of the software.
4. What Are the Methods of Software Testing?
There are two methods for testing software –
Static Testing refers to testing the software for bugs without running the code. It is usually performed at the initial stages of development to debug the software easily. It is carried out through both manual and automation testing.
Some of the things tested in static testing are mentioned below:
- Business Requirements Document
- Unit test cases
- Functional requirements
- Use cases
- Test data
- Prototype Specification Document
- Traceability Matrix Document
- User Manual
- Automation Scripts
Some benefits of Static Testing are mentioned below:
- It helps to identify defects in the code.
- It is a fast and easy way to identify and rectify errors.
- It is possible to find mistakes at initial stages with Static Testing.
Dynamic Testing refers to testing the software for functionality, memory usage, and overall operation by running the code. Dynamic testing aims to assess software performance with dynamic factors or non-constant variables.
For example, suppose you are testing a social media log-in platform.
There are two fields available – “Username” and “Password.”
If the “Password” field is restricted to alphabets only and you put “LH123”, the system will show “error.” But, if you put “Leeway,” the system will accept it.
This shows that the code is functioning dynamically with different inputs.
Dynamic Testing aims to ensure the smooth functioning of the software after and while installing it.
Some advantages of Dynamic Testing are:
- It supports the analysis of applications.
- It reveals errors missed out by Static Testing.
- It ensures the quality of the software by making it mostly bug-free.
- It validates the findings of Static Testing.
- It can be implemented with any application.
Some disadvantages of Dynamic Testing are:
- It is time-consuming.
- It is costly.
5. What Are the Approaches to Software Testing?
There are mainly three approaches to Software Testing:
- White Box Testing
- Black Box Testing
- Grey Box Testing
White Box Testing
White box testing is also known as clear box testing/glass box testing/structural testing/open box testing.
Here, you know the design or code of the software. The purpose is to check the software’s functioning based on the code.
White box testing analyses the inner functioning of the system. You need to have the programming knowledge to perform it.
Some advantages of White Box Testing are:
- It can be performed at the initial stages.
- It is more thorough.
- It allows us to find hidden defects.
- It helps in code optimization.
- Maximum coverage is ensured due to knowledge of code.
Some disadvantages of White Box Testing are:
- It can be complicated.
- It requires highly skilled resources.
- Tools to perform white-box testing may not be readily available.
Black Box Testing
Black box testing is also known as Behavioral Testing.
Here, you are not aware of the internal design or code.
It aims to find bugs in the functions, interface, data structures, behavior, initialization, and termination.
Some advantages of Black Box Testing are:
- It exposes inconsistencies in specifications.
- There is no need to understand programming.
Some disadvantages of Black Box Testing are:
- Tests may be tough to design.
- Many bugs can go undetected.
Black Box Testing is further classified into two categories:
- Functional Testing
- Non Functional Testing
1. Functional Testing – Functional testing aims to verify that there are no gaps between developed features/functions and the required features/functions.
The QA team writes functional test cases. After providing the input, the outputs are verified and the actual results are compared with the expected outcomes.
Functional testing is performed at various levels like
- Unit Testing
- Integration Testing
- System Testing
- Acceptance Testing
The levels of testing will be discussed later in this article.
2. Non-Functional Testing – Non-functional testing aims to focus on the non-functional parts of the software like:
- Memory leaks
Non Functional Testing is performed at all levels.
Grey Box Testing
Grey box testing is a mixture of white-box testing and black-box testing. Detailed design documents and requirements are accessible to you.
Some advantages of Grey Box Testing are:
- It provides combined benefits of white box testing and black-box testing.
- Grey box testers can develop more intelligent tests.
- Developers and testers have clear goals while testing.
- The overall quality of the software is enhanced.
6. What Are the Levels of Software Testing?
There are mainly four levels of testing:
- Unit Testing
- Integration Testing
- System Testing
- Acceptance Testing
A unit is the tiniest testable component of the software. At this level, individual units of the software are tested.
The aim is to ensure the proper functioning of each unit.
It usually has a few inputs and a single output. White Box Testing and Functional Testing are applicable at this level.
For Example, Suppose you are manufacturing a sipper water bottle. You will manufacture and assess each unit like the straw, the cap, and the bottle separately.
Some advantages of unit testing are:
- For unit testing, easier codes are made.
- It increases the confidence to modify and maintain codes.
- It ensures faster development.
- It is cost-effective.
- The process is made agile.
- It improves the quality of code.
- It simplifies debugging.
At this level, individual units are grouped for testing. This level aims to detect errors in the integrated units’ interaction.
For Example, Suppose you are manufacturing a sipper water bottle. After examining each unit separately, you will assess its functioning together. You will ensure that the cap fits the bottle, or the straw fits in the lid.
All three approaches to software testing are applicable at this level.
Some advantages of Integration Testing are:
- It ensures that units function together.
- It can be done at the initial stages.
- It can be done with individual modules of the software.
- It conveniently finds issues at the system-level (e.g., integration defects)
At this level, the integrated software is tested wholly.
This level aims to assess the conformity of the software with the established requirements and end-to-end testing. Black Box Testing is usually applicable at this level.
For example, you assess the sipper bottle’s quality and if it meets the needs of the end-user properly.
Some advantages of system testing are:
- It assesses the system against the user’s work, practical and technical requirements.
- It assists in identifying maximum bugs.
- It heightens the team’s confidence by ensuring that the software is functioning smoothly as a whole.
- It detects bugs missed out by Unit Testing and Integration Testing.
At this level, the software is assessed for acceptability. The software is verified against the requirements to ensure it is adequate for delivery.
For example, once the sipper water bottle is entirely manufactured, you assess its acceptability and adequacy before delivering it for sale.
Some advantages of Acceptance Testing are:
- It ensures that the present conditions meet the expected needs.
- It reduces the risk of identifying major bugs during production.
- It identifies bugs left out during the earlier levels.
- It ensures the proper functioning of the end product.
7. What Are the Different Testing Process Models?
There are majorly four types of testing process models-
- Traditional Waterfall Development Model
- Agile Development Model
- V Model
- Spiral Model
Traditional Waterfall Development Model
Winston Royce introduced the waterfall development model in 1970. It is one of the oldest models.
It is a sequential model that pre-defines all stages of the Software Development Life Cycle.
According to this model:
- An independent group of testers does testing.
- Each stage must be finished for the next step to begin.
- Stages cannot overlap.
- Testing is done once all the functional requirements have been developed.
The Waterfall Development model was used mostly in the past. Even though it facilitates the formation of detailed documentation at each step, Waterfall Development Model offers a set of disadvantages that make it undesirable to use today.
- Bugs can be fixed only during the testing stage.
- It is an undesirable approach for complex projects.
- Documentation takes up a lot of time.
- The testing stage arrives very late in the Software Development Life Cycle in this model.
- The client’s feedback is not considered in the development phase.
- Errors that arise after the completion of the software development process cause a lot of trouble.
The Agile Model is the emerging approach to Software Development. It focuses mainly on breaking down tasks into smaller iterations and not involving long term planning.
Software engineers design unit tests at each step. Every failing test is followed by writing codes to make it pass.
Tests are continuously conducted and updated as new bugs are discovered.
The objective of this model is to support continuous integration and decrease defect rates.
Some advantages of the Agile Development Model are:
- Frequent deliveries
- Constant communication with clients
- Efficient designs
- Requirement fulfillment
- Changes can be made anytime.
This model carries out the development and test execution operations parallelly. It is a rigid model. It divides the software testing process into five stages:
- Unit Testing
- Integration Testing
- Regression Testing
- System Testing
- Acceptance Testing
This model is convenient to use as planning and designing are done before coding. Hence, it is time effective and increases the odds of success.
Spiral Model is identical to the Agile model. However, it focuses on risk analysis.
The assembly of needs and risk analysis is done at the base and upper spirals form over it.
The odds of avoiding risks increase as the model focuses on risk analysis. It is a preferable model for complex software as new functionalities can be added later.
However, it is costly and requires experts to perform the risk analysis.
8. What Are the Various Tools for Software Testing?
Today, a lot of software testing tools hold great significance, especially for automation testing.
The following list includes the top 10 Software Testing tools of 2020:
- Selenium is a testing tool for web applications. Selenium helps to create complicated and progressive automation scripts. It is usually the base of most of the software testing tools. It is an open-source tool that supports a significant amount of programming languages. It reduces time by supporting parallel test execution.
- Appium is a testing tool mainly for mobile applications. It is easy to install and use. It supports the automation of native, hybrid, and mobile web applications for both IOS and Android. In recent years, Appium has become one of the best mobile automation testing tools. It automates any mobile app supported by any language and test framework. It is open-sourced.
- Katalon Studio
- It is an automation testing tool that supports both web and mobile-based applications. It can be integrated with various tools like Jira, Git, Slack, qTest, etc. It shows versatility by running on Windows, macOS, and Linux. It has numerous built-in keywords to develop a variety of test cases. Minimum programming skills are needed to use this tool.
- It is a Behaviour Driven Development Tool. It is open-sourced and has remarkable users like PayPal and Canon. It supports numerous languages but only a web-based environment. Code can be executed on different frameworks and is written in simple English (known as Gherkin).
- HPE Unified Functional Testing
- HPE Unified Functional Testing makes functional testing easier and less costly by providing developers and testers with a common platform. It gives great automation testing solutions. Its scripting language is VBScript and it backs data-driven testing. It also offers cross-browser and multi-platform compatibility.
It can automate many applications. Some of them are:
- Worksoft is an automation testing tool for SAP. It provides the only code-free platform for continuous test automation. This tool can be deployed even in the implementation, maintenance, and up-gradation stages of the SAP project. It offers an in-built test-data management tool.
- This tool is primarily built to meet the requirements of large firms that handle crucial business processes. It offers DevOps and Agile continuation automation platforms.
- IBM Rational Functional Tester
- It is a commercial tool from IBM. This tool is primarily concerned with:
a) Automated Functional Testing
b) Regression Testing
c) Graphical User Interface Testing
d) Data-Driven Testing
- It offers a storyboard testing feature that helps you visualize and modify tests using application screenshots and natural language. It supports scripting languages like Java and VB.Net.
It also supports many development environments like Net, SAP, Java, etc.
- It is a commercial tool from IBM. This tool is primarily concerned with:
- Telerik Test Studio
- This tool offers an extensive test automation solution. It supports the testing of desktop, web, and mobile applications. It also provides cross-browser compatibility.
- Telerik Test Studio is an automation testing tool that enables scheduled tests, parallel test execution, and strong test reporting features. It supports two scripting languages – C# and VB.Net. It also has a feature of “Record and Playback Tool,” which is compatible with the Graphical User Interface (GUI), Performance, Load, and Application Programming Interface (API) Testing.
- Soap UI
- Soap UI is an open-source tool for functional testing. Even though it is not a testing tool for web or mobile app testing, it can be used for API Testing. It allows unsynchronized testing and easy reuse of scripts. It also has features like drag-and-drop and point-and-click test generation.
- It also supports various testing techniques like data-driven testing, regression testing, distributed testing, and keyword-driven testing.
9. What Are the Software Testing Deliverables?
Software Testing deliverables play an essential role in software testing. They are used during the project.
Relevant test deliverables must be sent to the client on time. They are:
Test Strategy is chosen based on the business requirement specifications.
It is an essential, high-rank management document developed by the test manager. It provides an overview of the software development cycle’s approach.
The test strategy document must include:
a) Test Objective
b) Test Scope
c) Testing Types
d) Testing Efforts and Costs
The test strategy document is a part of the Test Plan.
Test Plan and Estimation
The test plan is an elaborate document that acts as a road map for the whole project. It enables developers, managers, and clients to understand the testing process in detail. It also guides the testing team throughout the project.
a) Test Strategy
b) Test Objective
c) Test Criteria
d) Resource Planning
e) Schedule and Estimation
Test Estimation is a document that estimates the amount of effort needed in the project. The entire project is divided into smaller components and each component’s required effort is estimated.
i) Test Report: 20 man-hour
ii) Test Delivery: 30 man-hour
iii) Test Execution: 90 man-hour
Test Estimation leads to the formation of a test-schedule, which is also known as project management.
Test Scenario is an elaborate document of test cases that includes all functionalities of the software. Similar requirements are grouped to be performed.
Test scenarios discuss multiple ways to use the software. They aim to understand the software’s overall flow.
Test scenarios are prepared from the user’s viewpoint. Hence it is preferable to take inputs from clients, developers, or users.
The modification of test scenarios is convenient and independent. Hence it is easy to maintain.
For Example, test scenarios for a food delivery application would look like:
i) Check the “search restaurants” functionality.
ii) Check the “payments and refunds” functionality.
Test cases are a group of actions performed to evaluate one feature of the software.
Test cases include particular conditions, which assist the testing team in ensuring that the actual and expected results match.
Test cases are usually derived from test scenarios.
Some examples of test cases for a food delivery application would look like:
i) Check the behavior when the correct username and password are put in.
ii) Check the behavior when an incorrect username and password are put in.
iii) Check if the “error” message is displayed on payment failure.
Test Data refers to the data used to perform tests. It needs to be accurate and comprehensive to find errors and bugs properly.
Requirement Traceability Matrix
The requirement traceability matrix assists the testing team in setting every requirement with a test case. It helps the testing team to ensure that all the needs of the client have been met. It also helps the client to check on the testing process quickly.
Test Summary Report
As the name suggests, the test summary report summarizes the executed tests along with their results. It assists the client to understand and evaluate the entire testing process.
Some of the information which a test summary report must include are:
i) Testing Members
iv) Client Details
v) Test Approach used
vii) Defect Report
Test Closure Report
This report gives a detailed assessment of the entire testing process. This report implies that the testing procedure is coming to an end after executing tests and fixing bugs. The test manager usually makes this report. It also mentions all the exit criteria.
An incident report is raised when a bug is found while executing the final software.
For example, Suppose the final execution of a food delivery application is being performed, and it is found that the “change delivery address” feature is not working. Then an Incident Report is raised by the tester to the client, asking for permission to carry out a separate test case to deal with the bug.
10. What Are the Principles of Software Testing?
There are seven principles of Software Testing.
- Testing shows the presence of defects.
- Exhaustive testing is not possible.
- Early Testing: Testing should be started early to find detects first.
- Defect Clustering: A small number of modules usually contain most of the defects.
- Pesticide Paradox: Repeatedly conducting the same tests won’t find new flaws. Test cases should be regularly reviewed and revised to avoid the pesticide paradox.
- Testing is context-dependent.
- Absence of errors fallacy – Identifying and fixing bugs is useless if the system built is unusable.
11. What Qualities Should You Look Into Your Software Testing Team?
Here is a list of the qualities you should ensure your software testing team has:
- Contextual Adaptivity
The testing team should be open to adapt different software testing approaches according to the project’s context. Such flexibility comes in handy to increase the efficiency of the software.
- Programming Knowledge
Irrespective of the testing type being used, the testing team should have a certain amount of programming knowledge to assess and rectify the bugs more effectively.
- Understanding of Testing Techniques
Many testing teams lack the knowledge of the variety of testing techniques available. This should not be the case. You should ensure that the testing team you hire has a fair idea about all the options available.
- Understanding Business Requirements
The testing team should have a clear understanding of the purpose of the software being tested. When the team is aware of the client’s requirements, it can identify and rectify bugs in a better way.
- Good Communication Skills are crucial as they directly affect the understanding between the testing team and the client. The team must have exceptional verbal and written communication skills to eliminate the scope of misunderstandings in the requirements.
- Constant Learning
As the world is transforming digitally, new technologies and techniques are introduced every day. Hence, it is essential for the testing team always to be open to learning to stay updated about all the latest available options, which will help them do a better job.
- It is also imperative for the software testing team to have strong Logical Skills, firm Analytical Skills, and excellent Testing Skills to efficiently perform software testing.
No software is built perfectly. Every software always has a scope for improvement. Software Testing plays a vital role in ensuring that the most competent, effective, and majorly bug-free software is delivered to your clients.
Published at DZone with permission of Akash Takyar. See the original article here.
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