1. An apparatus for building a map, the apparatus comprising: an obstacle map builder to build an obstacle map on the basis of obtained obstacle detection information; a controller to build a feature map including a plurality of features, position information of the features, and information regarding degrees of uncertainty of the features on the basis of an amount of change in posture and an image obtained while a mobile robot moves, and localizing the mobile robot itself; a path generator to generate a moving path on the basis of the degrees of uncertainty of the features obtained by the mobile robot, wherein the path generator selectively generates the moving path from among a plurality of moving paths including an exploration path for reducing the degrees of uncertainty of the features and a self-localization enhancement path for reducing a degree of uncertainty of a position of the mobile robot, wherein the exploration path and the self-localization enhancement path are generated on the basis of the degrees of uncertainty of the features; and a drive controller to control the mobile robot to travel along the generated moving path, wherein the feature map and the obstacle map are updated on the basis of the amount of change in posture, the image, and the obstacle detection information obtained while the mobile robot travels along the generated moving path.