Recent advances in techniques for transferring and stacking single atomic layers have enabled the fabrication of van der Waals junctions of 2D materials. In this Short Course, we review the fabrication method and carrier transport properties of various van der Waals junctions of 2D materials such as graphene and transition metal dichalcogenides (TMDs) for future functional devices : (i) Graphene/h-BN with an extremely high carrier mobility exceeding 100,000 cm2/Vs at room temperature; (ii) Graphene/TMD/metal vertical FET with large current modulation exceeding 105 ON-OFF current ratio simultaneously with a large ON current density of 104 A/cm2; (iii) Fe0.25TaS2/Fe0.25TaS2 vdW magnetic tunnel junctions for spintronics; (iv) NbSe2/NbSe2 vdW Josephson junctions.