Why am I writing a post about a game that came out 8 years ago? It's been written about before, and you can read reviews on how to play Hanabi in many other places on the interwebs. Well, for one, because it's a great cooperative game as listed on my Best Cooperative Games List.
The other reason I'm writing about it is because in addition to it being a classic game, and a top notch, it's one of the best cooperative card games, I also believe this is a game about people and communication more than anything else. For me, Hanabi is more of an educational game and something I would classify as "work" more than play. While most of the games I play are strictly for fun, Hanabi is not a game I would play for fun.
Hanabi is a game I would play if I wanted to work on my communication style, or on being in tune with others. Or if I wanted to hone in on my non-verbal communication skills.
Now could be a good time to chat about the mechanics and how to play. Basically, you and up to to 4 other players are going to be pyrotechnicians and put on a great fireworks show that could go amiss. The "fireworks" or cards have to be put in color and number order from 1-5. Each player gets 4 or 5 cards, depending on the total number of players, and players do not get to see their own cards. Players hold their cards facing out, so that each player can see everyone else's cards, but not their own.
From here, player's can give information, play a card, or discard a card. Every time a player gives information they use a time token; discarding a card gets a token back. In this way, there is an added constraint to deal with, other than the fact that if you make a mistake, you get that much closer to an awful fireworks show.
In terms of the information you may give, you can give a player color information OR number information. You can point and say, "this card is green and this card is green." Or you can point and say "this card is a 2 and this card is a 2." You cannot point to a card and say "this is a green 2."
This is where the game gets really tricky. Not only are you trying to remember what you have in your hand and where it is (and remember, if you play a card, you pick up a new card), you are also assessing other player's cards and needing to provide helpful clues in the correct order, under certain constraints.
When playing this game, you may notice that you communicate really well with someone you already know, or you many observe how much miscommunication there is, and how one thing means something entirely different to someone else, or that something obvious to one person went completely over another player's head. Shocking!
Like I said, if you want to see how good you are at non-verbal communication and where you stand, or take a hard look at the difficulties in communication generally, play Hanabi.
There are also techniques that advanced players utilize and may discuss ahead of time. Certain 'rules' so to speak about what a certain clue may mean. High-level play so to speak. You can bring your Hanabi game to the next level, or you can play for the first time and see how much people miscommunicate in every day life.
For a full set of rules, see this pdf.