Gestell (or sometimes Ge-stell) is a German word used by twentieth-century German philosopher Martin Heidegger to describe what lies behind or beneath modern technology. Heidegger introduced the term in 1954 in The Question Concerning Technology, a text based on the lecture "The Framework" ("Das Gestell") first presented on December 1st 1949, in Bremen. It was derived from the root word stellen, which means "to put" or "to place" and combined with the German prefix Ge-, which denotes a form of "gathering" or "collection". The term encompasses all types of entities and orders them in a certain way. Heidegger applied the concept of Gestell to his exposition of the essence of technology. He concluded that technology is fundamentally Enframing (Gestell). As such, the essence of technology is Gestell. Indeed, "Gestell, literally 'framing', is an all-encompassing view of technology, not as a means to an end, but rather a mode of human existence". Heidegger further explained that in a more comprehensive sense, the concept is the final mode of the historical self-concealment of primordial φύσις. In defining the essence of technology as Gestell, Heidegger indicated that all that has come to presence in the world has been enframed. Such enframing pertains to the manner reality appears or unveils itself in the period of modern technology and people born into this "mode of ordering" are always embedded into the Gestell (enframing). Thus what is revealed in the world, what has shown itself as itself (the truth of itself) required first an Enframing, literally a way to exist in the world, to be able to be seen and understood. Concerning the essence of technology and how we see things in our technological age, the world has been framed as the "standing-reserve." Heidegger writes, Enframing means the gathering together of that setting-upon which sets upon man, i.e., challenges him forth, to reveal the real, in the mode of ordering, as standing-reserve. Enframing means that way of revealing which holds sway in the essence of modern technology and which is itself nothing technological.