Slytherin = Snake
Ravenclaw = Eagle
Hufflepuff = Badger
Gryffindor = Lion
The girls (and boys) dormitories are all located inside the common room of each house.
Griffindore: Rubies Slyterin: Emeralds Ravenclaw:Saphire Hufflepuff: Quartz
I believe only the Gryffindor House has a password, but maybe not. In book 7 when Harry was going with Luna into the Ravenclaw House it was not a password, but a question. If you answer it correctly you will enter if not you won't.
Each Hogwarts house has its own colours; Gryffindor's are red and gold, Ravenclaw blue and bronze, Hufflepuff yellow and black, Slytherin green and silver. Hogwarts itself is often represented by purple.
The "school for magic" in Harry Potter is Hogwarts School of Witchcraft and Wizardry. There are four houses and each one bears the name of the four founders of Hogwarts, respectively: Gryffindor, Hufflepuff, Ravenclaw, and Slytherin.
The four house colors of Hogwarts School of Witchcraft and Wizardry are Red and Gold (Gryffindor), Blue and Bronze (Ravenclaw), Green and Silver (Slytherin), Yellow and Black (Hufflepuff).*Note: In the film adaptations Ravenclaw is portrayed as blue and silver.
The symbols are universal and the names are different in each language
There are no overall symbols that represent America. Though each country has their own national symbols.
In the Harry Potter novels, the students at the school were sorted by the putting on the Sorting Hat. The Sorting Hat would then tell each student which Hogwarts House they would join.
Just in Hogwarts (it varies, depending on which book) there are a minimum of seven games, with a possible eighth if there is a point tie for last place. Outside of Hogwarts, we can't know because she never states just how many teams there actually are.
Key, The maps key shows all symbols with a brief explanation of each.
Yes, there are 7 players on a Quidditch team and 4 teams at Hogwarts. 7 multiplied by 4 equals 28. Those players are; 1 Keeper, 1 Seeker, 3 Chasers and 2 Beaters. One player on each team is also the captain.