Test Driven Development or Behavior Driven Development - A Fight Against

Test Driven Development or Behavior Driven Development - A Fight Against

In respect to software development, possibilities are you have caught behaviour-driven development (BDD) and test-driven development. Below we will get to know the definition of these two practices and also major differences between them. 


Behavior Driven Development (BDD)

A software development technique named, Behavior-driven development defines the behavior of the user before marking the test automation scripts or the code’s functional pieces. This method assures the generation of a shippable product at the sprint’s end in an Agile sprint. It includes the following:


  • In simple English jargon, the user’s behavior is defined by a business analyst or a product owner or QA. 

  • To run, on the contrary, the functional code, these are then transformed into automated scripts. 

  • The scripting of functional code then begins by the development team to assure that they get the green light from the automated test script. 

  • The code is then organized and refactored by the team of developers to give a tested outcome at the sprint’s end. 


Being driven by various tools like PowerTools, FitNesse, Docker, Cucumber, and so on, BDD’s test scripts are written in the simple English language in Wiki frameworks, Gherkin, etc. As it’s written in plain English, in the project, the stakeholders get a common stage. Thus, the risk of development of code that would reach the user’s acceptance behaviour will get reduced. 


Test-Driven Development (TDD)

A software technique, Test Driven Development (TDD) includes the scripting of the automated test cases before writing the functional sections of the code. In Agile methodologies, this holds the popularity as it encourages encouraging a shippable item at the sprint’s end. This process is further divided into various steps:


  • Based on the requirement documents, a developer marks an automated test case. 

  • These automated test scripts are executed by the development team against that is presently developed and this should be done, as still the implementation of the features is not attained. 

  • Starts by the development team, functional code is written to guarantee the automated test script offering a green light. 

  • Then, the code gets organized and refactor by the development team to give a tested deliverable as a outcome at the sprint’s end. 


Mostly marked in programming jargon like Ruby, Java, etc., test cases can also be written making the use of automation tools like Windmill, Watir, Selenium, etc. The test scripts are hard to be identified by the test owner or business analyst as programming languages are finalized to write them. 


BDD vs TDD

  • Since written in English, BDD is easily readable, on the contrary, TDD test cases are written in programming languages like Java, Ruby, etc.

  • For the end-users, the applications’ behaviour is explained by BDD, whereas, the focus is fixed on the implementation of the functionality by TDD. With less stress in BDD, the alteration in functionality can be supported, which is opposed in TDD. 

  • All the stakeholders are enabled by BDD to stand on the same page with the essentials which lead to easy acceptance but is not favoured by TDD.


In BDD, the central idea is the application’s behaviour, it targets the customer and compels the developers along with testers to try walking in the customer’s shoes. Such a scenario is not represented well by BDD if the actions remain unaffected to the end-user, but in TDD this purpose serves the best. 

It might not be possible to recognize what performs best globally for all the projects like various other practices of software development. BDD is accepted as the best mode to clutch all the actions of the user for the systems that are tamed by the end user’s action like the HR system or e-commerce website. TDD is believed to be a better solution for the systems holding data imports/exports, third-party API calls, etc.