BDD and Gherkin for Testers

Behavior-Driven Development (BDD) uses examples in plain language to describe behavior; Gherkin is the format (Given/When/Then) used to write those examples. As a QA, you can write scenarios in Gherkin and link them to automated steps. This post introduces BDD and Gherkin from a tester's perspective.

What is BDD?

BDD focuses on behavior and shared understanding: developers, QA, and product use the same examples. Examples are written in a structured, readable format (Gherkin) and can be automated so they double as living documentation and tests.

Gherkin in brief

• Feature: High-level capability (e.g. "User login").
• Scenario: One concrete example (e.g. "Successful login with valid credentials").
• Steps: Given (context), When (action), Then (outcome). Optional: And, But.

Example:

Feature: Login
  Scenario: Successful login with valid credentials
    Given the user is on the login page
    When the user enters valid email and password
    And the user clicks Sign in
    Then the user is on the dashboard

How testers use it

• Write scenarios: In Gherkin, in collaboration with product and dev; focus on behavior, not implementation.
• Automate: Map each step to code (e.g. Cucumber, Behave, SpecFlow). One step definition can be reused across scenarios.
• Living documentation: The same feature file is readable by humans and runnable by the automation framework.

Summary

• BDD = behavior and shared examples; Gherkin = Given/When/Then format for those examples.
• Testers write and maintain scenarios; step definitions connect them to automation.
• Use Gherkin for clarity and living documentation; keep scenarios focused on behavior, not UI details.