RoboPol is a photopolarimeter with 13’ x 13’ FOV deployed on the 1.3m telescope at the Skinakas Observatory in Greece. Collaborators include scientists from Caltech, Max-Planck (Bonn), Nicolaus Copernicus University, and IUCAA. Halfwave plates and Wollaston prisms are used to separate photons with orthogonal linear polarizations, and simultaneously produce four images on the CCD detector for each source in the focal plane. The photon counts in each “spot” are used to calculate the Stokes parameters of linear polarization. This novel, 4-channel design eliminates the need for multiple exposures with different halfwave plate positions, thus avoiding unmeasurable, errors due to sky changes between measurements and imperfect alignment of the halfwave plate. The primary science goal is to monitor the optical linear polarization of >100 gamma-ray bright blazars, which will allow to test models of the jet structure, composition, magnetic fields, and emission mechanism. RoboPol is additionally used to map the magnetic field in interstellar clouds and for a long-term monitoring of XBE stars.