Remove ambiguity in Edition 1 of this ETS. Method by which ITU-R System B Teletext, also known as World System Teletext (WST), may be carried in DVB bitstreams. This transport mechanism is intended to satisfy the following requirements: 1. Support the transcoding of Teletext data into the Vertical Blanking Interval (VBI) of analogue video, compatible with existing TV receivers with Teletext decoders. 2. Maximum data rate for each Teletext service is equivalent to 16 lines per field so that the service is always suitable for transcoding into the VBI. 3. Transmission mechanism capable of transmitting subtitles with accurate timing with respect to the video, i.e. within or near frame accuracy. A more general data transport mechanism for conveying new types of data services is outside the scope of this document, but the transport syntax specified here can also be adapted for other data.