Abstract: I review recent and not so recent works aiming to understand whether a nominally repulsive Coulomb interaction can give rise to superconductivity. I discuss a generic scenario of the pairing, put forward by Kohn and Luttinger back in 1965, and then review modern studies of the electronic mechanisms of superconductivity in the lattice systems, which model cuprates, Fe-based superconductors and graphene-based systems, both twisted and non-twisted. I show that in all cases the pairing can be viewed as an extension of Kohn-Luttinger mechanism, despite that the pairing symmetries are different. I discuss under what condition the pairing occurs and rationalize the need to go beyond perturbation theory. I also discuss most recent work on the pairing near a quantum-critical point, particularly the interplay between superconductivity and non-Fermi liquid physics.