The broadcast data set contains messages intended for terminal users. The messages are saved in the broadcast data set using the SEND command or the SEND subcommand of OPERATOR. The broadcast data set contains two sections: the mail section and the notices section. The mail section contains messages intended for particular users; the notices section contains messages intended for all users.

By default, 100 records that are each 129 bytes long are set aside for broadcast messages in the broadcast data set. You can change the number of records for your installation's processing needs. For more information, see Changing the amount of space reserved for notices.