Dances happen a lot at Hogwarts, so the Headmaster had decided to add a room to the Entrance Level called the Ballroom. The ballroom serves as a purpose for holding all sorts of ceremonial celebrations and other honorary assemblies.

Well all students and staff of Hogwarts School have to eat at least three times a day. So the Great Hall was placed here to serve as a dining room for everyone to sit down with their houses and have their meals. This is also where the Sorting takes place for new arrivals.

This room is a place for the staff members of Hogwarts can come at any time of the day to sit back and work on lessons, have a cup of coffee for those who like it, or snack when they are a bit hungry. This also serves as a place for the staff to just hang out with each other.

This is where the Goblet of Fire is held. Those who want to place their names in the cup to have a shot at the Tri-Wizard Tournament. However, there is an age line. Students fifteen and older may enter. Others under the age may only watch until they are old enough to enter.