diff --git a/lib/database/base_entity.dart b/lib/database/base_entity.dart
new file mode 100644
index 0000000..1a0b7b5
--- /dev/null
+++ b/lib/database/base_entity.dart
@@ -0,0 +1,19 @@
+abstract class BaseEntity{
+  static String id = 'id';
+  static String title = 'Title';
+  static String creationDate = 'CreationDate';
+  static String lastEditDate = 'LastEditDate';
+  
+  static String get getId{
+    return id;
+  }
+  static String get getTitle{
+    return title;
+  }
+  static String get getCreationDate{
+    return creationDate;
+  }
+  static String get getLastEditDate{
+    return lastEditDate;
+  }
+}
\ No newline at end of file
diff --git a/lib/database/identifiers/enum/color.dart b/lib/database/identifiers/enum/color.dart
new file mode 100644
index 0000000..f3a721f
--- /dev/null
+++ b/lib/database/identifiers/enum/color.dart
@@ -0,0 +1,14 @@
+enum Color {
+  none,
+  red,
+  orange,
+  yellow,
+  green,
+  blue,
+  purple,
+  pink,
+  brown,
+  grey,
+  black,
+  white,
+}
diff --git a/lib/database/identifiers/enum/priority.dart b/lib/database/identifiers/enum/priority.dart
new file mode 100644
index 0000000..8e9a138
--- /dev/null
+++ b/lib/database/identifiers/enum/priority.dart
@@ -0,0 +1,7 @@
+enum Priority{
+  none,
+  low,
+  medium,
+  moderate,
+  high
+}
\ No newline at end of file
diff --git a/lib/database/identifiers/tag.dart b/lib/database/identifiers/tag.dart
new file mode 100644
index 0000000..229ead5
--- /dev/null
+++ b/lib/database/identifiers/tag.dart
@@ -0,0 +1,6 @@
+import 'enum/color.dart';
+
+class Tag {
+  static String title = "";
+  Color color = Color.none;
+}
diff --git a/lib/database/note.dart b/lib/database/note.dart
new file mode 100644
index 0000000..ece0167
--- /dev/null
+++ b/lib/database/note.dart
@@ -0,0 +1,8 @@
+import 'base_entity.dart';
+
+class Note extends BaseEntity{
+  static String id = BaseEntity.getId;
+  static String Title = BaseEntity.getTitle;
+  static String CreationDate = BaseEntity.getCreationDate;
+
+}
\ No newline at end of file
diff --git a/lib/database/promemoria.dart b/lib/database/promemoria.dart
new file mode 100644
index 0000000..baa8ddd
--- /dev/null
+++ b/lib/database/promemoria.dart
@@ -0,0 +1,11 @@
+import 'base_entity.dart';
+import 'identifiers/enum/priority.dart';
+
+class Note extends BaseEntity{
+  static String id = BaseEntity.getId;
+  static String title = BaseEntity.getTitle;
+  static String creationDate = BaseEntity.getCreationDate;
+  static String expirationDate = 'expirationDate';
+  Priority priority = Priority.low;
+}
+