The paper is an overview of the H-mode physics studies on TCV. Historically, ELMy H-modes were obtained with ohmic heating only (q95<3). With the installation of a X3 ECRH system, the operational range increased to low pedestal collisionalities, in the ITER range, allowing pedestal pressures to increase by a factor 3-4. In 2015, a neutral beam injector (H or D) was installed and H-modes at q95>3 are now routinely obtained. The pedestal database developed for EUROfusion is presented and used within the paper.