The 'describe' keyword in javascript

So I am a newbie in javascript and i had been going through some one else's code and I found this..

describe('deviceready', function() {
    it('should report that it fired', function() {
        spyOn(app, 'report');
        app.deviceready();
        expect(app.report).toHaveBeenCalledWith('deviceready');
    });
});

What I don't understand is: What exactly does the describe keyword do?

info:
- Its a phonegap application
- We are using the spine.js and jQuery libraries

Solution 1:

Describe is a function in the Jasmine testing framework. It simply describes the suite of test cases enumerated by the "it" functions.

Also used in the mochajs framework.

Solution 2:

Describe is not part of Javascript, it is a function defined in the library you used (namely Jasmine)

Solution 3:

According to the Jasmine Documentation

The describe function is for grouping related specs, typically each test file has one at the top level. The string parameter is for naming the collection of specs, and will be concatenated with specs to make a spec's full name.