Abstract
How did thefirst cosmic web of matter organize into the first stars and galaxies? This question is intimately connected to the question of whether the different primordial environment produced noticeable effects concerning the properties of the so-called First Stars. It is in the Milky Way halo that the oldest and most metal-poor stars in the Universe are found, born at times or equivalent redshifts still out of reach for the deepest surveys of primordial galaxies. These stars contain a memory of the unique nucleosynthesis in the First Stars and can thus be used as fossil records. In this work we show some recent observations that are believed to unveil some interesting properties of the First Stars.
