Firebase Realtime Database

what is firebase databse?
what can it be used for?
realtime database in action
database structure best practices

““:
“golden”: 1.618
“fog”: true
“palindrome”: “tacocat”
“messages”: “message1”: “name”:”person”, “text”:”Hello?”
“message2”: “name”:”Individual”, “text”:”Hi!”

node should be “child” and “parent

{
	"questions": {
		"ABCDakarandomkey": {
			"question": "Who was the 13th president of the United States?"
			"choice_1": "Millard Fillmore",
			"choice_2": "Zachary Taylor",
			"choice_3": "Franklin Pierce",
			"choice_4": "James K. Polk",
			"answer" :"choice_1"
		},
		"EFGHakarandomkey":{
			"question": "In what year was the first gasoline combustion engine invented?",
			"choice_1":"1769",
			"choice_2":"1886",
			"choice_3":"1807",
			"choice_4":"1864",
			"answer": "choice_4"
		}
	},
	"players":{
		"user_key_1":{
			"name":"Person",
			"opponents":{
				"IJKLakarandomkey":"user_key_2",
				"MNOPakarandomkey":"user_key_6"
			},
			"questions":{
				"ABCDakarandomkey": "Correct",
				"EFGHakarandomkey": "Incorrect"
			}
		},
		"user_key_2": {
			"name": "Mai",
			"opponents": {
				"QRAAakarandomkey": "user_key_1",
				"SQUEakarandomkey": "user_key_6"
			},
			"questions": {
				"ABCDakarandomkey":"Incorrect",
				"EFGHakarandomkey":"Incorrect"
			}
		}
	},
	"opponents": {
		"couple_Key_1": "user_key_1_user_key_2",
		"user_1": "user_key_1",
		"user_2": "user_key_2",
		"winner": "user_key_1"
	}
}