This sample is demonstrating how to use Everest REST API client in the browser, using traditional global variable export. If you don't use an AMD-module loader, this is the way to use Everest.
In that configuration, Everest exports itself as a global variable : window.everest
or
window.ê
EverestJs is also usable as an AMD-module (with a module loader like require.js).
Check the AMD sample to see how it works.
This sample triggers a call to the github api after instantiating a new Rest client. The call result is displayed in the panel under the form.
Open your browser javascript console and check the source to see what is going on under the hood.