Research and commentary have been addressed to distinctions regarding problem gambling on the basis of differences in the types of gambling in which individuals engage, such as symptom severity, co-occurring conditions, psychological correlates, and demographic differences. Some progress has been made at the level of the whole game. For example, electronic gaming machine users are more often female and more prone to depressive disorders as well as gambling disorder. Players of other games, such as poker and sports betting, are typically male and prone to substance use disorders. A promising recent trend, however, is to create taxonomies to analyze relevant structural game characteristics that predict gambling problems in a theoretically grounded way. Temporal characteristics such as speed and duration of games have received the most attention, but other relevant characteristics include a skill element, online (Internet) format, and various superficial characteristics. These efforts remain at an early stage, and further development is needed.