There is no single definition of Digital Humanities. Brett Bobley, Director of the National Endowment for the Humanities Office of Digital Humanities, a key grant agency in this emerging field, commented in a 2009 interview:
Under the digital humanities rubric, I would include topics like open access to materials, intellectual property rights, tool development, digital libraries, data mining, born-digital preservation,multimedia publication, visualization, GIS, digital reconstruction, study of the impact of technology on numerous fields, technology for teaching and learning, sustainability models, media studies, and many others. (See full interview with Kathleen Smith and Michael Gavin, 2009)
Other definitions are floated at digital humanities meetings on a regular basis. See, for instance, definitions linked from the Association for Computers and the Humanities.
Here are examples of methods used in the digital humanities.