Planets acquire their spin from the angular momentum of the rotating gas clouds from which they form, as this momentum is conserved during coalescence. However, the relationship between orbital and spin angular momentum is complex, and collisions can alter a planet's rotation direction, leading to some planets spinning retrograde. The Moon's rotation is tidally locked with Earth, which complicates the influence of impacts on its spin direction. While conservation of angular momentum is a key factor, it does not fully explain the specific spin characteristics of planets due to the interplay of various forces and processes during formation. Ongoing research continues to explore these complexities in planetary spin dynamics.