1. A computer-implemented method for browsing hierarchically structured data, comprising: displaying on a display a first-level circular user interface object with at least one first-level selector object, wherein the first-level circular user interface object is a first graphical user interface object with a first circular form, wherein the at least one first-level data object represents a first level of the hierarchically structured data, wherein the first-level circular user interface object has an outer circular edge with a first diameter, wherein the first diameter is equal to an initial diameter; and responsive to receiving a first selection of one of the at least one first-level selector object and by operation of a computer: rotating the first-level circular user interface object to orient the at least one first-level selector object to stop at a predefined orientation used to align all selected selector objects on the same circular angle; indicating the first selection on the display in response to receiving the selection; decreasing the first diameter in response to receiving the selection; and displaying a second-level circular user interface object with at least one second-level selector object in response to the first selection, wherein the second-level circular user interface object is a second graphical user interface object with a second circular form, wherein the second-level circular user interface is operable for receiving a second selection of one of the at least one-second level selector objects, wherein the at least one second-level data object represents a second-level branch of a second level of the hierarchically structured data, wherein the first branch is determined by the first selection, wherein the second-level circular user interface object has an inner circular edge and an outer circular edge, and wherein the inner circular edge of the second-level circular user interface object is attached to the outer circular edge of the first-level circular user interface object.