Orleans, once in Calgary, and once in north Houston. Public courses are also offered each year the weekend prior to the SEG Annual Meeting. Section-sponsored courses are sponsored by SEG sections or affiliated societies, and contract courses are sponsored by individual companies or organizations. Generally one or two days long, most courses can be expanded up to 5 days if desired. Distinguished Lecturer The Distinguished Lecturer (DL) program is offered two times per year. The Spring DL visits a minimum of 15 locations each year to present a lecture suitable for a lunch or dinner meeting of a local section or university group. Each year the DL is recorded and posted to the Distinguished Lecturers Presentation Library for free viewing by members and the public. The Fall DL is sponsored jointly with the American Association of Petroleum Geologists (AAPG). SEG and AAPG alternate years administering the program. Honorary Lecturer SEG also offers the Honorary Lecturer (HL) program. The HL program is a companion program to the DL with a focus to transfer knowledge within a region. The regional focus strengthens services SEG provides to an expanding global membership. Lectures may be given in English or a language appropriate to the region. The regions are Central and South America, Europe, Middle East and Africa, North America, the Pacific South, and South and East Asia. SEG Wiki The SEG Wiki launched in the winter of 2011, seeded with SEG's number one bestseller, Robert E. Sheriff's Encyclopedic Dictionary of Applied Geophysics. All entries in the SEG Wiki can be modified and improved by SEG members. All content in the wiki is published under the Creative Commons Attribution-ShareAlike 3.0 Unported License (CC-BY-SA), the same as Wikipedia. Additional highlights in the SEG Wiki include: Biographies: Many of the pioneers in the development of exploration geophysics, including past SEG presidents, editors of Geophysics, and SEG Honors and Awards' winners. Open data: This section documents geophysical data that is readily available for download from the internet, via mail, or through special request. In early October 2014, SEG's second bestselling book, Seismic Data Analysis, by Öz Yilmaz was added to the wiki. The geophysical tutorial series debuted in the February 2014 issue of The Leading Edge. The tutorials appear every other month to serve as a brief exploration of a geophysical topic. See also List of geoscience organizations American Association of Petroleum Geologists (AAPG) American Geophysical Union (AGU)