Get all combos of strings in 2 arrays

1_with_tap.rb

first_names = %w(rebecca jessica mabel)
middle_names = %w(jean lynn orla amelia)

[].tap do |names|
  first_names.each do |first_name|
    middle_names.each do |middle_name|
      names << "#{first_name} #{middle_name}"
    end
  end
end

2_with_product.rb

first_names = %w(rebecca jessica mabel)
middle_names = %w(jean lynn orla amelia)

first_names.product(middle_names).map do |name_product|
  name_product.join(" ")
end