diff --git a/app/models/entity.rb b/app/models/entity.rb
new file mode 100644
index 0000000..91b546f
--- /dev/null
+++ b/app/models/entity.rb
@@ -0,0 +1,3 @@
+class Entity < ApplicationRecord
+  belongs_to :user
+end
diff --git a/app/models/group.rb b/app/models/group.rb
new file mode 100644
index 0000000..8b606b6
--- /dev/null
+++ b/app/models/group.rb
@@ -0,0 +1,3 @@
+class Group < ApplicationRecord
+  belongs_to :user
+end
diff --git a/app/models/user.rb b/app/models/user.rb
new file mode 100644
index 0000000..296c408
--- /dev/null
+++ b/app/models/user.rb
@@ -0,0 +1,4 @@
+class User < ApplicationRecord
+  has_many :entities
+  has_many :groups
+end
diff --git a/db/migrate/20230912134007_create_users.rb b/db/migrate/20230912134007_create_users.rb
new file mode 100644
index 0000000..e1fda72
--- /dev/null
+++ b/db/migrate/20230912134007_create_users.rb
@@ -0,0 +1,8 @@
+class CreateUsers < ActiveRecord::Migration[7.0]
+  def change
+    create_table :users do |t|
+      t.string :name
+      t.timestamps
+    end
+  end
+end
diff --git a/db/migrate/20230912134307_create_groups.rb b/db/migrate/20230912134307_create_groups.rb
new file mode 100644
index 0000000..e24c2eb
--- /dev/null
+++ b/db/migrate/20230912134307_create_groups.rb
@@ -0,0 +1,11 @@
+class CreateGroups < ActiveRecord::Migration[7.0]
+  def change
+    create_table :groups do |t|
+      t.string :name
+      t.string :icon
+      t.references :user, null: false, foreign_key: true
+
+      t.timestamps
+    end
+  end
+end
diff --git a/db/migrate/20230912134451_create_entities.rb b/db/migrate/20230912134451_create_entities.rb
new file mode 100644
index 0000000..9184927
--- /dev/null
+++ b/db/migrate/20230912134451_create_entities.rb
@@ -0,0 +1,11 @@
+class CreateEntities < ActiveRecord::Migration[7.0]
+  def change
+    create_table :entities do |t|
+      t.string :name
+      t.float :amount
+      t.references :user, null: false, foreign_key: true
+
+      t.timestamps
+    end
+  end
+end
diff --git a/spec/models/entity_spec.rb b/spec/models/entity_spec.rb
new file mode 100644
index 0000000..f513ed6
--- /dev/null
+++ b/spec/models/entity_spec.rb
@@ -0,0 +1,5 @@
+require 'rails_helper'
+
+RSpec.describe Entity, type: :model do
+  pending "add some examples to (or delete) #{__FILE__}"
+end
diff --git a/spec/models/group_spec.rb b/spec/models/group_spec.rb
new file mode 100644
index 0000000..be100cf
--- /dev/null
+++ b/spec/models/group_spec.rb
@@ -0,0 +1,5 @@
+require 'rails_helper'
+
+RSpec.describe Group, type: :model do
+  pending "add some examples to (or delete) #{__FILE__}"
+end
diff --git a/spec/models/user_spec.rb b/spec/models/user_spec.rb
new file mode 100644
index 0000000..47a31bb
--- /dev/null
+++ b/spec/models/user_spec.rb
@@ -0,0 +1,5 @@
+require 'rails_helper'
+
+RSpec.describe User, type: :model do
+  pending "add some examples to (or delete) #{__FILE__}"
+end