20. The apparatus of claim 19 , wherein the composition information includes position information for positioning a text subtitle represented by the text subtitle data on a display.
19. An apparatus for reproducing a text subtitle stream recorded on an optical disc, the apparatus comprising: a pickup unit configured to reproduce data recorded on the optical disc; and a controller operatively coupled to the pickup unit and configured to control a reproduction of the text subtitle stream, wherein the controller is further configured to control the pickup unit to read a first segment included in the text subtitle stream, the first segment includes first style information, and the first style information includes at least one of composition information and rendering information for a region including text subtitle data, wherein the controller is further configured to control the pickup unit to read a second segment included in the text subtitle stream, and the second segment includes the text subtitle data and second style information, wherein the second segment is linked to the first segment, and the second style information includes font information for the text subtitle data, wherein the font information is declared at a beginning of at least a portion of the text subtitle data being affected by the font information, wherein the second segment includes a length indicator indicating a length of the at least the portion of the text subtitle data, wherein the controller is further configured to reproduce the text subtitle data using the first and second style information, wherein each of the first segment and the second segment includes a segment identifier identifying the first segment and the second segment, respectively, and wherein the controller is further configured to reproduce the text subtitle data using the first and second style information.