System D
System D is a manner of responding to challenges that requires one to have the ability to think quickly, to adapt, and to improvise when getting a job done. The term gained wider popularity in the United States after appearing in the 2006 publication of Anthony Bourdain's "The Nasty Bits". Bourdain references finding the term in Nicolas Freeling's memoir, "The Kitchen", about Freeling's years as a Grand Hotel cook in France. The term derives from the French term . The letter "D" refers to any one of the French nouns , or (French slang). The verbs and  mean to "make do", to "manage", especially in an adverse situation. Basically, it refers to one's ability and need to be resourceful. In "Down and Out in Paris and London", George Orwell described the term as something the lowest-level kitchen workers, the "s", wanted to be called, indicating that they were people who would get the job done, no matter what. In recent literature on the informal economy, System D is the growing share of the world's economy which makes up the underground economy, which has a projected GDP of $10 trillion. The informal economy is  usually considered as one part of a dual economy. The concept of dual economy is where the economy is divided into two parts - the formal and the informal. The formal economy refers to all economic activities that operate within the official legal framework and are regulated by the government. In common parlance, it is understood as enterprises and citizens who pay taxes on all generated incomes. The reason, Neuwirth refers to this kind of an economy as a DIY economy or system D is because of the self reliance of the members within this sector. Due to lack of documentation , such as citizenship proof, tax id number, identity or address proof, people working in this sector are usually left with no way to seek support from their governments. This means that they are unable to access formal institutions which require documentation, and forces them to be self-reliant. This is not to be confused with autarky or self reliant economies. Economists define self-sufficiency or self-reliance as the state of not requiring any aid, support, interaction or trade with the outside world. It is generally believed that a fully self-dependent economy or autarky is not possible in  today's world. The term in different languages. There are a range of terms in other languages describing similar circumstances. Examples for those are in German, in Swiss German, ("Trick 3") in Finnish, in Afrikaans, "to hack it" in English, in European Portuguese, in Brazilian Portuguese, in Urdu, Hindi, and Punjabi, in Swahili, in Tagalog and in Congolese French.