VBB is the public transport association for the Berlin-Brandenburg area and offers mobility for the region using regional/commuter trains, the local railway (S-Bahn), underground trains (U-Bahn), buses, trams and ferries.
The S-Bahn on one hand helps you cover large areas of the city within little time. In the city center, there are two major routes: East-West and North-South. Additionally, using the "Ring" (circle line) you can move quickly between stations at the edge of the inner city area.
The U-Bahn, on the other hand, has a dense net of stations, allowing you to move quickly between spots in the city center as well as to more peripherial places.
The different means of transport are operated by several companies. BVG (underground, buses, trams and busses), Deutsche Bahn AG (regional/commuter trains) and S-Bahn Berlin GmbH (local railway) are the major public transport operators.
The Berlin area is subdivided into three tariff zones:
Usually it is not necessary to travel between more than two zones. The most basic tickets for single trips within the A and B zones are as cheap as EUR 2.70, which allows the use of any means of transport (multi-modal) towards your destination within two hours time.
There are other types of tickets (for example day and week-passes). Find more information on purchasing and validating your ticket and fares on VBB's website.
Important: Do not forget to validate your ticket prior to entering a train. There is a 60 EUR fine on free-riding, intentional or unintentional. As for buses and trams, however, you can purchase and validate your ticket in the vehicle.
Most accomodation is situated in zones A and B. Usually you won't need to travel between more than two zones. If you plan on travelling by public transport, it would probably be most convenient to find accomodation close to the conference venues or to the stations served by underground line U3. See the list of public transport connections at the conference venues: