What is a "Länder" in German ?
It designates the "country" or "state" level depending on the context.
What is a "coup d'état " ?
It is when you try to get the power at the head of a government in a violent and non-democratic way It litteraly means " hit of the State" in French.
What's my value proposition ? ( when starting a business )
That’s what business-school types call a “value proposition”—fancy wording for “why the hell you should spend money and time on my product or service.” Every company, project and employee should have a value prop—preferably a clear and measurable one—though plenty are wanting.