Before the conference, Assange claimed Wikileaks had information that could damage Hillary Clinton's USA presidential campaign. While he did not reveal any of that data during the meeting, Assange did say that Wikileaks hopes to publish secret documents and information every week for the next ten weeks up to the November 8 election. The materials will include topics on war, arms, oil, Google, and the USA election.
During the conference, Assange showcased his newly written books, spoke of Wikileak's 10th anniversary. and answered questions from the press.
to showcase - to show something to a large group of people
press conference - a meeting of reporters and journalists organized by someone who wants to talk to the public
the press - newspaper, internet, tv, reporters (i.e. the media)