The convention is spread over four days, with the highlights coming late in the day, to coincide with prime time television viewing in the US.
The convention is intended to have a "town hall" atmosphere, with participants answering questions sent in by supporters around the US. Proceedings can be watched live on the convention website.
Barack Obama's speech on Thursday, where he will accept the party's nomination for the presidential election, falls on the 45th anniversary of Martin Luther King's "I have a dream" speech.
Theme: Barack Obama's life story and his commitment to "change".
The main speech was given by Barack Obama's wife, Michelle Obama. Her brother, Craig Robinson, and Mr Obama's half-sister, Maya Soetoro-Ng, also made appearances.
Veteran senator and Democratic Party icon Ted Kennedy, who is being treated for a brain tumour, also spoke. His niece, Caroline Kennedy, paid him an emotional tribute.
Jesse Jackson is not speaking at the convention - after criticising Mr Obama for speaking down to black people - but his son, Jesse Jackson Junior, appeared on Monday.
Theme: The economy, and Hillary Clinton...
Hillary Clinton makes the main speech of the day, on the economy and what the Democratic Party considers to be the "failed policies" of the last eight years.
Mark Warner, the former governor of Virginia and a possible rising star in the Democratic Party, will make what is referred to as Tuesday's "keynote address". This is the speech that turned Mr Obama into a star of the 2004 convention.
Perhaps to emphasise the fact that not all women Democratic voters backed Hillary Clinton in the primaries, a number of leading female Obama supporters are taking the podium on Monday and Tuesday. Senator Claire McCaskill of Missouri and Amy Klobuchar of Minnesota, and House Speaker Nancy Pelosi speak on Monday. On Tuesday it is the turn of Kansas governor Kathleen Sebelius and Arizona governor Janet Napolitano, among others.
A vote is expected to be held on Tuesday on the party's platform for the election.
Theme: Foreign policy and security
Senator Joe Biden, chosen by Barack Obama as his running-mate partly on account of his foreign policy experience, is the main speaker.
He has a hard act to follow - former president Bill Clinton, whose speech will be closely scrutinised for signs of lingering resentment over the bruising primary campaign, which ended in defeat for his wife.
Commentators are expecting both men to lay into Mr Obama's Republican rival for the presidency, John McCain.
The roll-call vote, in which delegates will have the chance to vote for Mrs Clinton as the party's nominee, also takes place on Wednesday. Mrs Clinton is expected to ask her supporters on Wednesday morning to vote for Mr Obama.
Mr Obama will join the convention on Wednesday, after spending the first part of the week campaigning in battleground states.
Mr Obama makes the final speech of the convention in the 76,000-capacity Invesco Field, at the Mile High stadium (so named, because Denver is situated one mile above sea level). The last Democratic candidate to make his nomination acceptance speech in a stadium was John F Kennedy.
The convention website says Mr Obama "will communicate the urgency of the moment, highlight the struggles the American people are facing and call on Americans to come together to change the course of our nation."
Another headline speaker on the final day is former vice-president, and Nobel peace prize winner, Al Gore.
This may also be the day when the convention confirms Joe Biden as Mr Obama's running mate.