Goals of academic historians as well as museum and archive professionals are to explore history, publish or disseminate their findings and teach others. Archivists and museum professionals also have the added responsibility of caring for, preserving and documenting their collections and making them accessible to the public. Historians use the web to do research as well as to share ideas and publish.
The 5 venues or forms in which historans might work could be oral history, documents & archival sources (both primary & secondary), objects/material culture, site analysis (archeology & historic preservation), and direct observation of an event (current history in the making) which I guess could also include Internet, televison, and radio broadcasts as well as other media recordings such as the 9/11 cell phone recordings.