After that you have all embedded files of this input file with the following naming:
theora_<ID>.ogv: This is the video stream encoded with the theora codec. The <ID> is the stream ID that is created by the encoder to uniquely identify this stream.
vorbis_<ID>.oga: This is the audio stream encoded with the vorbis codec. The <ID> is the stream ID that is created by the encoder to uniquely identify this stream.
unknown_<ID>.ogv: This is an unknown stream, that could not be interpreted. The <ID> is the stream ID that is created by the encoder to uniquely identify this stream.
All files are fully playable with your favoured video or audio player (except the streams, that are uninterpreted).