Dunjonquest is a series of single-player, single-character fantasy computer role-playing games from Automated Simulations (later known known as Epyx). The Temple of Apshai and related expansions, later repackaged as a "Trilogy", are the best known and most widely ported games of the series. The games were heavy on strategy and pen & paper RPG-style rules and statistics.
Games in this series are not to be confused with roguelikes as the Dunjonquest maps were not random (although some games like Sorcerer of Siva might place the character in a random starting spot in higher difficulty settings). Additionally, the Temple of Apshai and Hellfire Warrior games and related expansions for each placed significant importance on the uniqueness of each room the player entered through use of printed room descriptions.
The Dunjonquest games were ported across a wide variety of late 1970s and early 1980s home computers.
A spinoff of the Apshai series of Dunjonquest titles, Gateway to Apshai was action-oriented rather than periodic turn-based and required a joystick and quick reflexes to play. Other than the name and fantasy setting there was little similarity between the Dunjonquest titles and Gateway to Apshai. Gateway to Apshai was meant as a prequel to the Apshai series and had a background story printed in the accompanying player's guide.
Source: Wikipedia, "Dunjonquest (series)", available under the CC-BY-SA License.