Cucumber is an automated test runner that executes tests written in a Domain-Specific Language (DSL) called Gherkin. Gherkin allows you to write tests in plain language, usually in a behavior-driven way, which can be read and understood by anyone, even if they are not technically-minded.
There are many Cucumber implementations for different languages and platforms, such as Ruby, Java, Python, C++, PHP, Groovy, Lua, Clojure, .NET and, of course, JavaScript. The JavaScript implementation is available as an npm package, so let's add it to our project:
$ yarn add cucumber --dev
We are now ready to write the specification for our first feature.
