This year the conference is taking place in Brighton. Ministers will speak today - with a closed door meeting with the Prime Minister due this afternoon at 4.30pm.
Conference is described by the TUC itself -
"The policy making body of the TUC is the annual Congress which meets for four days each year during September. Each affiliated union can send delegates to Congress - the larger the union, the more it can send. At Congress 'motions' (resolutions for debate) are proposed and discussed. These form the basis of the TUC's work for the next year."
Further details can be found at http://www.tuc.org.uk/congress/index.cfm?mins=578