  Electrical manipulation of magnetic order by current-induced spin torques
lays the foundation for spintronics. One promising approach is encoding
information in the N\'eel vector of antiferromagnetic (AFM) materials,
particularly to collinear antiferromagnets with the perpendicular magnetic
anisotropy (PMA), as the negligible stray fields and terahertz spin dynamics
can enable memory devices with higher integration density and ultrafast speed.
Here we demonstrate that the N\'eel order information in a prototypical
collinear AFM insulator with PMA, Cr2O3, can be reliably readout via the
anomalous Hall effect and efficiently switched by the spin-orbit torque (SOT)
effect with a low current density of 5.8*106 A/cm2. Moreover, using Cr2O3 as a
mediator, we electrically switch the magnetization of a Y3Fe5O12 film
exchange-coupled to the Cr2O3 layer, unambiguously confirming the N\'eel order
switching of the Cr2O3 layer. This work provides a significant basis for
developing AFM memory devices based on collinear AFM materials with PMA.
