MPEG-2 Transport Stream
The MPEG2 Transport Stream Format specifies how to encapsulate MPEG2 Elementary Stream Packets, the MPEG2 Multiplexer procedure, and how to add additional information like PSI Tables and Sync Information.
Normally, in DVB-T (and others?) a transport stream contains more than one program stream and therefore more than one program.
Multiple programs is a page describing various software solutions to record more than one program at a time.