After a brief introduction to the concept of formal Deformation Quantisation, we shall focus on constructions of star products, enhancing links between star products and linear connections. We first consider the symplectic context: we recall how any natural star product on a symplectic manifold determines a unique symplectic connection and we recall Fedosov's construction which yields a star product, given a symplectic connection. In the more general context, we consider universal star products, which are defined by bidifferential operators expressed by universal formulas for any choice of a linear torsionfree connection and of a Poisson structure. We recall how formality implies the existence (and classification) of star products on a Poisson manifold. We present Kontsevich formality on R d and we recall how globalisation of this result proves the existence of a universal star product. Finally, we present some special constructions of star products on some symplectic manifolds endowed with special connections.