One game series that often includes dating, with the goal of marriage, is the farming sim series Harvest Moon.
These games often feature a day-night cycle with a time scheduling system that provides context and relevance to character interactions, allowing players to choose when and if to interact with certain characters, which in turn influences their responses during later conversations.
While bishōjo games make up the bulk of dating sims, other types of games exist.
When the game ends, the player either loses the game if he failed to properly win over any of the girls, or "finishes" one of the girls, often by having sex with her, marrying her (as in Magical Date), and/or achieving eternal love.
This gives the games more replay value, since the player can focus on a different girl each time, trying to get a different ending.
Games that try to simulate real-world activities (like driving vehicles or living the life of someone else) with as much realism as possible.