Hamburg’s public transportation network, HVV, offers rapid transit and regional rail lines, three U-Bahn (metro) lines, S-Bahn lines and several Metro- and City buslines.
Apart from the regular one-way tickets, there are single and group day tickets which are worth to be considered if you want to take more than one trip a day. Tickets can be purchased at every metro station (before getting on the metro though) or directly on the bus. See here for more information about the ticket system, time tables and possible connections >>
StadtRAD is a public bicycle renting system that offers an ecologic alternative to making your way through the city centre. Once registered, you can easily rent a bike at one of the 116 stations located in the extended city centre. Use is free for half an hour, afterwards, you are charged 4cents / per minute (8 cents from minute 61), maximum charge for a day is 12€. You pay at the terminal upon returning the bike using EC or credit card. Information and registration on the following webpage: www.stadtrad.hamburg.de
If you plan to do tourism in Hamburg or stay some extra days before or after the conference, you can also consider getting the Hamburg Card. The card provides free public transportation and discounts on many tourist activities like museums, harbour cruises, and theatres. Prices starting from 8.90€ for a single day ticket. See also www.hamburg-tourism.de