diff --git a/app/src/main/java/net/micode/notes/data/Notes.java b/app/src/main/java/net/micode/notes/data/Notes.java
index 8b91a0d..92d7479 100644
--- a/app/src/main/java/net/micode/notes/data/Notes.java
+++ b/app/src/main/java/net/micode/notes/data/Notes.java
@@ -18,6 +18,11 @@ package net.micode.notes.data;
 
 import android.net.Uri;
 
+/**
+ * 便签类中包含了一些自定义常量（字符串，整型）
+ * 抽象了便签列和数据列接口
+ * 定义了文本便签、询问便签实现了便签列和数据列接口
+ */
 public class Notes {
     public static final String AUTHORITY = "micode_notes";
     public static final String TAG = "Notes";