Surgical tool systems and methods

A surgical robot system comprising:

• a robot base having a display;
• a robot arm coupled to the robot base, wherein movement of the robot arm is electronically controlled by the robot base;
• and
• an end-effector, coupled to the robot arm, containing one or more end-effector tracking markers;
• wherein the robot base is in electronic communication with the robot arm and the end effector,
• wherein the one or more end-effector tracking markers are configured to be detected by a camera system and the display is configured to indicate a location of the end-effector in relation to at least one of the robot base and the robot arm,
• wherein the robot arm is configured to selectively move the end-effector along the x, y, and z axes and configured for selective rotation about one of the x, y, and z axes,
• wherein the robot arm does not provide six degrees of freedom,
• wherein the robot arm is configured to position the end-effector in location to optimize the placement of pedicle screws.