what is hash in ruby code example

Example 1: how to make a new hash ruby

my_hash = Hash.new #=> { }
# OR
my_hash = {}

Example 2: how ruby methods take in a hash of attributes

def create(name:, age:, gender:) #Main lesson on this line
	some_variable = SomeClass.new(name, age, gender)
    some_variable.save #save is an instance method undefined here
    some_variable
end