Some people say that the most important thing about a game is that it’s fun. I agree with this, but the thing is ‘fun’ means different things to different people. Here are some of them:

Casual Games

These games have little or no penalty and cater to ‘everyone’. If none of the other games interest you, then you’re a casual gamer. A mistake might only cost you some time. Examples are those building games on social media, or rpgs without perma-death. You can play them when you’re tired and enjoyment usually comes from growing or improving something (whether it’s a restaurant, city or character).

Hardcore Games

These games require your full attention. They’re extremely hard and/or have permanent death. Examples include rogue-like games but anything with a steep learning curve or deep mechanics. People enjoy these games because they want a challenge as well as the satisfaction of overcoming those challenges. They think casual games are meaningless because anything people do in them can be done by anyone with enough time (or money). 

Reflex/Action Games

Any game that requires you to react quickly. Examples include platformers, fighting games or shooters. They’re similar to hardcore games in that they can be hard but don’t have to be or might not be as punishing. The thrill here is being in the action/moment because things are always happening.

Puzzle/Strategy Games

Games which favor careful thinking, they usually give you plenty of time to think, plan and make your move. Examples include card games and games with turns/phases. The opposite of action games, people play these game when they want to exercise/train their brain – like doing Sudoku or playing chess.

Horror Games

Any game with the main aim of trying to scare the player or creep them out. The same people who enjoy these games watch horror movies or ride roller coasters at theme parks. Why? I don’t know because I’m not one of them.

Story based Games

Story is not particularly strong in video games because a strong story usually means weak gameplay. The best example of this is visual novels. People play these games for a good story that might be a little bit interactive. (If they just wanted a good story, they’d probably just read a book).

Competitive Games

Any game where you compete against other players. Almost any game can be made competitive. Even causal games can have rankings between players to see who’s progressed the furthest. Sometimes competition is what drives players to keep playing because it’s fun to keep striving to be on top.

Conclusion

As an indie developer it’s important to let people know what kind of game you made so the right people who would think that it’s fun would be interested in trying it out. It’s also good to keep in mind what type of ‘fun’ you’re going for so you don’t go off track.