Definition & What is Software Quality: This post is one of the continuation posts of software testing tutorial series. In our last post, we have discussed different software testing terminology grocery. And in this post, we are going to talk about software quality.
Before discussing software quality latest try to understand:
what is the software definition?
Software is a set of instructions, data or programs tells the computer how to work. This can be anything from an application to games to spreadsheets. Two types of software are application software, and another one is system software.
What is a quality definition?
Quality refers to how good something is compared to other similar things. You can say like its a degree of excellence. But when used to describe software, it refers to a defect-free, delivered on time, within the budget, meet the requirements or expectations, and that should be maintainable.
What is Software Quality?
As per the Wikipedia software quality means
In the context of software engineering, software quality measures how well software is designed (quality of design), and how well the software conforms to that design (quality of conformance). It is often described as the ‘fitness for purpose’ of a piece of software.
and as per the ISO 8402-1986 standard defines quality as
the totality of features and characteristics of a product or service that bears its ability to satisfy stated or implied needs.
The quality of software can be defined by verifying the ability of the software against the user requirement. When it comes to a software product, it must satisfy all the functionality mentioned in the software requirement specification (SRS) document.
Sometimes we are not considering a software product as a quality product, although it satisfies all the requirements mention in the SRS document. For example, consider a software product whose every functionality is working as per the requirement, but the user interface of the software product is unusable. Even though it is working as expected, but we cannot say this is a quality product.
We can calculate the Software quality is based on the number of variables. Those variables can be divided into external & internal quality criteria. The external quality represents the user experiences during the running the software application, whereas internal quality refers to code-dependent, and that are not visible to the end-user.
Software Quality is the confirmation that the software is meeting its requirements. And we can check whether the software is meeting the quality or not by using two factors like Validation and Verification.
Attributes of Software Quality
Some key aspects are there which country the software quality of the product, that is:
- Good design
- Good functionality
- Good after-sales service
- Value for money
Good Design: As we know that the good looks & style of the application can attract the customers. It’s essential that the application has a good design, user-friendly, and meet all the customer’s requirements. Few everyday things consider the right colour for the application, font size, and styling of the web elements.
Good functionality: With Good looks of the application, the functionality of the application should work as expected. There should not be any deviation between the actual result and the expected result.
Reliable (acceptable level of breakdowns or failure): After complete the Good looks and Good functionality, we have to test the application reliable. For example, – Lets there is a system that can store employee details, and it should not fail after a certain number of entry of the employees. This is called reliability.
Consistency: As we know that an application can run on multiple platforms, so its more important that your application behaves the same in all platforms. And that is called Consistency.
Durable (lasts as long as it should): The developed application should be run for a long time without failing that is called durable. For example- by using a web application, you can insert 100 employees’ details. Still, after 100 employees, if you have entered more employee details, then it should continue without any functional breaks of the application.
Good Service: The very first thing that comes to the picture is Service after release or ship the product to the product owner. So it’s very important to provide the best service to make the customer happy and satisfied.
Scalability: How easy is it to extend a feature? Or to add a new one? Or to add extra cores, or increase the size of the cluster the application runs on? Again, this is all about software architecture and anticipating future needs.
we have discussed several aspects of Software Quality like reliability, testability, the maintainability of code, and the rate of delivery. Testing is the basic way to measure all aspects of software quality, regardless of how quickly software must be released. The pressure to release software on time calls for the adoption of more software test automation, especially for GUI testing, which can be arduous.
Testing on its own is not enough to check and improve on software quality, though. It’s also important to use high-quality test metrics when evaluating the software. Test metrics measure the quality of any software testing effort. Without the right test metrics, errors are more likely to infiltrate production.
High-quality software results from a combination of comprehensively testing the main drivers of software quality and using test metrics to ensure the testing effort is effective.
We have discussed how we can get a quality software product, and for getting a quality product, we have to follow the above aspects.
What is the software quality model?
Following the book, the essential aspects of quality software products. But sometimes we need to analyze or do you want to measure the quality of software. So to measure the quality of software, we have to follow some software quality models.
mainly there are three software quality models which are accessible and acceptable when it comes to measuring the software quality, that are:
- McCall’s Quality Model
- Boehm quality model
- Dromey’s quality model
Mc call’s model
This model was first introduced by us Air Force to measure the software quality in 1977. the main aim of this model is to fill the gap between user and developers by focusing are the number of software quality factors that indicates the view of both users and developers.
Mccall’s quality model classifies all the software requirements into 11 software quality factors. Again, those 11 factors are grouped into three different categories: product operation, product division, and product transition factors:
- Product operation factors − Correctness, Reliability, Efficiency, Integrity, Usability.
- Product revision factors − Maintainability, Flexibility, Testability.
- Product transition factors − Portability, Reusability, Interoperability.
Boehm Quality Model
This software quality model introduced in the year 1978. this is what type of hierarchical model high-level characteristics. This model measures the software quality of a software product based on specific characteristics. based on software requirements, this model defined three primary uses, and those primary users are like:
- As-is utility, the extent to which the as-is software can be used (i.e., ease of use, reliability, and efficiency).
- Maintainability, ease of identifying what needs to be changed as well as ease of modification and retesting.
- Portability, ease of changing software to accommodate a new environment.
Again, these three primary uses had quality factors associated with them; 7 quality factors are the next level of Boehm’s hierarchical model.
- Portability, the extent to which the software will work under different computer configurations (i.e., operating systems, databases, etc.).
- Reliability, the extent to which the software performs as required, i.e., the absence of defects.
- Efficiency, optimum use of system resources during correct execution.
- Usability, ease of use.
- Testability, ease of validation, that the software meets the requirements.
- Understandability, the extent to which the software is easily comprehended with regard to purpose and structure.
- Flexibility, the ease of changing the software to meet revised requirements.
Dromey’s quality model
Dromey’s model is mainly focussed on the attributes and sub-attributes to connect properties of the software to the quality attributes
There are three principal elements to this model
- Product properties that affect the quality
- High-level quality attributes
- Linking the properties with quality attributes
We hope after reading this post, you have got an idea about what is the software quality and how to get a quality product for the client or the customer. After this article, you can read our other articles of software testing tutorial why following this link.