diff --git a/.idea/checkstyle-idea.xml b/.idea/checkstyle-idea.xml
index 6d6a80d..4f70595 100644
--- a/.idea/checkstyle-idea.xml
+++ b/.idea/checkstyle-idea.xml
@@ -3,7 +3,7 @@
   <component name="CheckStyle-IDEA">
     <option name="configuration">
       <map>
-        <entry key="checkstyle-version" value="8.13" />
+        <entry key="checkstyle-version" value="8.14" />
         <entry key="copy-libs" value="false" />
         <entry key="location-0" value="BUNDLED:(bundled):Sun Checks" />
         <entry key="location-1" value="BUNDLED:(bundled):Google Checks" />
diff --git a/app/src/main/java/ir/textmining/app/model/TagsLegend.java b/app/src/main/java/ir/textmining/app/model/TagsLegend.java
new file mode 100644
index 0000000..c55a1ed
--- /dev/null
+++ b/app/src/main/java/ir/textmining/app/model/TagsLegend.java
@@ -0,0 +1,139 @@
+package ir.textmining.app.model;
+
+import android.graphics.Color;
+import android.view.View;
+
+import androidx.annotation.NonNull;
+import androidx.appcompat.widget.AppCompatTextView;
+
+import com.google.android.material.card.MaterialCardView;
+import com.google.gson.annotations.SerializedName;
+import com.mikepenz.fastadapter.FastAdapter;
+import com.mikepenz.fastadapter.items.AbstractItem;
+
+import java.util.List;
+
+import butterknife.BindView;
+import butterknife.ButterKnife;
+import ir.textmining.app.R;
+
+public class TagsLegend extends AbstractItem<TagsLegend, TagsLegend.MyViewHolder> {
+
+  private Long id;
+
+  @SerializedName("PersianName")
+  private String persianName;
+
+  @SerializedName("Description")
+  private String description;
+
+  @SerializedName("Shortcut")
+  private String shortcut;
+
+  @SerializedName("Color")
+  private String color;
+
+  @SerializedName("Title")
+  private String title;
+
+  public Long getId() {
+    return id;
+  }
+
+  public void setId(Long id) {
+    this.id = id;
+  }
+
+  public String getPersianName() {
+    return persianName;
+  }
+
+  public void setPersianName(String persianName) {
+    this.persianName = persianName;
+  }
+
+  public String getDescription() {
+    return description;
+  }
+
+  public void setDescription(String description) {
+    this.description = description;
+  }
+
+  public String getShortcut() {
+    return shortcut;
+  }
+
+  public void setShortcut(String shortcut) {
+    this.shortcut = shortcut;
+  }
+
+  public String getColor() {
+    return color;
+  }
+
+  public void setColor(String color) {
+    this.color = color;
+  }
+
+  public String getTitle() {
+    return title;
+  }
+
+  public void setTitle(String title) {
+    this.title = title;
+  }
+
+  @NonNull
+  @Override
+  public MyViewHolder getViewHolder(@NonNull View view) {
+    return new MyViewHolder(view);
+  }
+
+  @Override
+  public int getType() {
+    return R.id.fastadapter_item_adapter;
+  }
+
+  @Override
+  public int getLayoutRes() {
+    return R.layout.item_tag_legend;
+  }
+
+
+  protected static class MyViewHolder extends FastAdapter.ViewHolder<TagsLegend> {
+    View view;
+    @BindView(R.id.title_text_view)
+    AppCompatTextView titleTextView;
+    @BindView(R.id.description_text_view)
+    AppCompatTextView descriptionTextView;
+    @BindView(R.id.card_view)
+    MaterialCardView cardView;
+
+    MyViewHolder(View view) {
+      super(view);
+      ButterKnife.bind(this, view);
+      this.view = view;
+    }
+
+    @Override
+    public void bindView(@NonNull TagsLegend item, @NonNull List<Object> payloads) {
+      titleTextView.setText(String.format("%s", item.getPersianName()));
+      cardView.setCardBackgroundColor(Color.parseColor(item.getColor()));
+      descriptionTextView.setText(item.getDescription());
+      if (item.getTitle().equals("O")) {
+        titleTextView.setTextColor(Color.BLACK);
+        descriptionTextView.setTextColor(Color.BLACK);
+      } else {
+        titleTextView.setTextColor(Color.WHITE);
+        descriptionTextView.setTextColor(Color.WHITE);
+      }
+    }
+
+    @Override
+    public void unbindView(@NonNull TagsLegend item) {
+      titleTextView.setText(null);
+    }
+
+  }
+}
\ No newline at end of file
diff --git a/app/src/main/java/ir/textmining/app/ui/activity/MainActivity.java b/app/src/main/java/ir/textmining/app/ui/activity/MainActivity.java
index 2a0d97f..0956528 100644
--- a/app/src/main/java/ir/textmining/app/ui/activity/MainActivity.java
+++ b/app/src/main/java/ir/textmining/app/ui/activity/MainActivity.java
@@ -40,6 +40,7 @@
 import ir.textmining.app.ui.fragment.AboutFragment;
 import ir.textmining.app.ui.fragment.SelectTagFragment;
 import ir.textmining.app.ui.fragment.SettingsFragment;
+import ir.textmining.app.ui.fragment.TagLegendFragment;
 import ir.textmining.app.util.AppUtil;
 import ir.textmining.app.util.Constant;
 import ir.textmining.app.util.MyApplication;
@@ -236,6 +237,11 @@ public void nextSentence() {
     getSentence();
   }
 
+  @OnClick(R.id.legend_button)
+  public void showLegend() {
+    AppUtil.showFragment(new TagLegendFragment(), getSupportFragmentManager());
+  }
+
   private void showSkeleton() {
     skeletonScreen = Skeleton.bind(chipGroup)
         .shimmer(true)
diff --git a/app/src/main/java/ir/textmining/app/ui/fragment/TagLegendFragment.java b/app/src/main/java/ir/textmining/app/ui/fragment/TagLegendFragment.java
new file mode 100644
index 0000000..7050b0d
--- /dev/null
+++ b/app/src/main/java/ir/textmining/app/ui/fragment/TagLegendFragment.java
@@ -0,0 +1,97 @@
+package ir.textmining.app.ui.fragment;
+
+import android.app.Dialog;
+import android.os.Bundle;
+import android.view.LayoutInflater;
+import android.view.View;
+import android.view.ViewGroup;
+import android.view.Window;
+import android.view.WindowManager;
+
+import androidx.annotation.NonNull;
+import androidx.appcompat.widget.AppCompatTextView;
+import androidx.fragment.app.DialogFragment;
+import androidx.recyclerview.widget.DefaultItemAnimator;
+import androidx.recyclerview.widget.GridLayoutManager;
+import androidx.recyclerview.widget.RecyclerView;
+
+import com.mikepenz.fastadapter.FastAdapter;
+import com.mikepenz.fastadapter.adapters.ItemAdapter;
+
+import java.util.List;
+
+import butterknife.BindView;
+import butterknife.ButterKnife;
+import butterknife.OnClick;
+import io.objectbox.Box;
+import io.objectbox.BoxStore;
+import ir.textmining.app.R;
+import ir.textmining.app.model.NerStandardTagsItem;
+import ir.textmining.app.model.TagsLegend;
+import ir.textmining.app.util.AppUtil;
+import ir.textmining.app.util.MyApplication;
+
+public class TagLegendFragment extends DialogFragment {
+  @BindView(R.id.title)
+  AppCompatTextView title;
+  @BindView(R.id.recyclerView)
+  RecyclerView recyclerView;
+  private Box<NerStandardTagsItem> tagsItemBox;
+  private FastAdapter<TagsLegend> mFastAdapter;
+  private ItemAdapter<TagsLegend> mItemAdapter;
+
+
+  @Override
+  public View onCreateView(@NonNull LayoutInflater inflater, ViewGroup container,
+                           Bundle savedInstanceState) {
+    View view = inflater.inflate(R.layout.fragment_tag_legend,
+        container, false);
+    ButterKnife.bind(this, view);
+    initVariables();
+    setUpRecyclerView();
+    handleTagItems();
+    return view;
+  }
+
+  private void initVariables() {
+    BoxStore boxStore = MyApplication.getBoxStore();
+    tagsItemBox = boxStore.boxFor(NerStandardTagsItem.class);
+  }
+
+  private void setUpRecyclerView() {
+    RecyclerView.LayoutManager mLayoutManager = new GridLayoutManager(getActivity(), 1);
+    recyclerView.setLayoutManager(mLayoutManager);
+    recyclerView.setItemAnimator(new DefaultItemAnimator());
+    mItemAdapter = new ItemAdapter<>();
+    mFastAdapter = FastAdapter.with(mItemAdapter);
+    recyclerView.setAdapter(mFastAdapter);
+  }
+
+  private void handleTagItems() {
+    List<NerStandardTagsItem> tagsItems = tagsItemBox.getAll();
+    mItemAdapter.clear();
+    mItemAdapter.add(AppUtil.convertToTagsLegend(tagsItems));
+  }
+
+  @NonNull
+  @Override
+  public Dialog onCreateDialog(Bundle savedInstanceState) {
+    Dialog dialog = super.onCreateDialog(savedInstanceState);
+    dialog.requestWindowFeature(Window.FEATURE_NO_TITLE);
+    dialog.setCancelable(true);
+    WindowManager.LayoutParams lp = new WindowManager.LayoutParams();
+    lp.copyFrom(dialog.getWindow().getAttributes());
+    lp.width = WindowManager.LayoutParams.MATCH_PARENT;
+    lp.height = WindowManager.LayoutParams.MATCH_PARENT;
+    dialog.getWindow().setAttributes(lp);
+    return dialog;
+  }
+
+  @OnClick(R.id.close_button)
+  void close() {
+    dismiss();
+    if (getFragmentManager() != null) {
+      getFragmentManager().popBackStack();
+    }
+  }
+}
diff --git a/app/src/main/java/ir/textmining/app/util/AppUtil.java b/app/src/main/java/ir/textmining/app/util/AppUtil.java
index c912b41..4f59f27 100644
--- a/app/src/main/java/ir/textmining/app/util/AppUtil.java
+++ b/app/src/main/java/ir/textmining/app/util/AppUtil.java
@@ -15,11 +15,15 @@
 
 import com.blankj.utilcode.util.SnackbarUtils;
 
+import java.util.ArrayList;
+import java.util.List;
+
 import io.objectbox.Box;
 import ir.textmining.app.R;
 import ir.textmining.app.model.AuthInfo;
 import ir.textmining.app.model.NerStandardTagsItem;
 import ir.textmining.app.model.NerStandardTagsItem_;
+import ir.textmining.app.model.TagsLegend;
 
 public class AppUtil {
 
@@ -83,4 +87,19 @@ public void onClick(View v) {
       }
     }, 100);
   }
+
+  public static List<TagsLegend> convertToTagsLegend(List<NerStandardTagsItem> tagsItems) {
+    List<TagsLegend> tagsLegends = new ArrayList<>();
+    for (NerStandardTagsItem item : tagsItems) {
+      TagsLegend tagsLegend = new TagsLegend();
+      tagsLegend.setColor(item.getColor());
+      tagsLegend.setDescription(item.getDescription());
+      tagsLegend.setId(item.getId());
+      tagsLegend.setPersianName(item.getPersianName());
+      tagsLegend.setShortcut(item.getShortcut());
+      tagsLegend.setTitle(item.getTitle());
+      tagsLegends.add(tagsLegend);
+    }
+    return tagsLegends;
+  }
 }
diff --git a/app/src/main/res/layout/content_main.xml b/app/src/main/res/layout/content_main.xml
index 85be5ff..bda0a99 100644
--- a/app/src/main/res/layout/content_main.xml
+++ b/app/src/main/res/layout/content_main.xml
@@ -17,14 +17,6 @@
         android:orientation="horizontal"
         android:padding="@dimen/spacing_large">
 
-        <androidx.appcompat.widget.AppCompatTextView
-            android:layout_width="0dp"
-            android:layout_height="wrap_content"
-            android:layout_weight="1"
-            android:text="@string/sentence_label"
-            android:textAppearance="@style/TextAppearance.MaterialComponents.Body1"
-            android:textStyle="bold|italic" />
-
         <com.google.android.material.button.MaterialButton
             android:id="@+id/next_sentence_button"
             style="@style/Widget.MaterialComponents.Button"
@@ -36,6 +28,21 @@
             app:cornerRadius="6dp"
             app:icon="@drawable/ic_navigate_next_black_24dp"
             app:iconTint="@android:color/white" />
+
+        <View
+            android:layout_width="@dimen/spacing_large"
+            android:layout_height="0dp" />
+
+        <com.google.android.material.button.MaterialButton
+            android:id="@+id/legend_button"
+            style="@style/Widget.MaterialComponents.Button.OutlinedButton"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:layoutDirection="locale"
+            android:text="@string/legend_label"
+            android:textAllCaps="false"
+            app:cornerRadius="6dp"
+            app:icon="@drawable/ic_info_outline_black_24dp" />
     </LinearLayout>
 
     <View
@@ -45,6 +52,15 @@
         android:layout_marginEnd="@dimen/spacing_xlarge"
         android:background="@color/grey_10" />
 
+    <androidx.appcompat.widget.AppCompatTextView
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:paddingStart="@dimen/spacing_large"
+        android:paddingEnd="@dimen/spacing_large"
+        android:text="@string/sentence_label"
+        android:textAppearance="@style/TextAppearance.MaterialComponents.Body1"
+        android:textStyle="bold|italic" />
+
     <androidx.core.widget.NestedScrollView
         android:layout_width="match_parent"
         android:layout_height="match_parent"
diff --git a/app/src/main/res/layout/fragment_tag_legend.xml b/app/src/main/res/layout/fragment_tag_legend.xml
new file mode 100644
index 0000000..4937612
--- /dev/null
+++ b/app/src/main/res/layout/fragment_tag_legend.xml
@@ -0,0 +1,64 @@
+<?xml version="1.0" encoding="utf-8"?>
+<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:app="http://schemas.android.com/apk/res-auto"
+    xmlns:tools="http://schemas.android.com/tools"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent"
+    android:background="@color/overlay_dark_50"
+    android:clickable="true"
+    android:focusable="true"
+    android:layoutDirection="locale"
+    tools:context=".ui.activity.MainActivity">
+
+    <com.google.android.material.card.MaterialCardView
+        android:layout_width="match_parent"
+        android:layout_height="match_parent"
+        android:layout_gravity="center"
+        android:layout_marginStart="@dimen/spacing_large"
+        android:layout_marginTop="@dimen/spacing_large"
+        android:layout_marginEnd="@dimen/spacing_large"
+        android:layout_marginBottom="@dimen/spacing_large"
+        app:cardCornerRadius="10dp"
+        app:cardElevation="6dp">
+
+        <LinearLayout
+            android:layout_width="match_parent"
+            android:layout_height="match_parent"
+            android:orientation="vertical">
+
+            <LinearLayout
+                android:layout_width="match_parent"
+                android:layout_height="wrap_content"
+                android:layout_gravity="center_horizontal"
+                android:orientation="horizontal"
+                android:paddingStart="@dimen/spacing_large"
+                android:paddingEnd="@dimen/spacing_large">
+
+                <androidx.appcompat.widget.AppCompatTextView
+                    android:id="@+id/title"
+                    android:layout_width="0dp"
+                    android:layout_height="wrap_content"
+                    android:layout_marginTop="@dimen/spacing_large"
+                    android:layout_weight="1"
+                    android:text="@string/tag_legend_label"
+                    android:textAppearance="@style/Base.TextAppearance.AppCompat.Subhead" />
+
+                <androidx.appcompat.widget.AppCompatImageButton
+                    android:id="@+id/close_button"
+                    android:layout_width="?attr/actionBarSize"
+                    android:layout_height="?attr/actionBarSize"
+                    android:background="?attr/selectableItemBackgroundBorderless"
+                    android:tint="@color/grey_60"
+                    app:srcCompat="@drawable/ic_close_black_24dp" />
+            </LinearLayout>
+
+            <androidx.recyclerview.widget.RecyclerView
+                android:id="@+id/recyclerView"
+                android:layout_width="match_parent"
+                android:layout_height="match_parent"
+                android:scrollbars="vertical"
+                android:scrollingCache="true" />
+
+        </LinearLayout>
+    </com.google.android.material.card.MaterialCardView>
+</LinearLayout>
\ No newline at end of file
diff --git a/app/src/main/res/layout/item_tag_legend.xml b/app/src/main/res/layout/item_tag_legend.xml
new file mode 100644
index 0000000..2a7240f
--- /dev/null
+++ b/app/src/main/res/layout/item_tag_legend.xml
@@ -0,0 +1,41 @@
+<?xml version="1.0" encoding="utf-8"?>
+<com.google.android.material.card.MaterialCardView xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:app="http://schemas.android.com/apk/res-auto"
+    xmlns:tools="http://schemas.android.com/tools"
+    android:id="@+id/card_view"
+    android:layout_width="match_parent"
+    android:layout_height="wrap_content"
+    android:layoutDirection="locale"
+    app:cardCornerRadius="6dp"
+    app:cardElevation="4dp">
+
+    <LinearLayout
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:orientation="vertical"
+        android:padding="@dimen/spacing_large">
+
+        <androidx.appcompat.widget.AppCompatTextView
+            android:id="@+id/title_text_view"
+            android:layout_width="match_parent"
+            android:layout_height="wrap_content"
+            android:textAppearance="@style/TextAppearance.MaterialComponents.Body1"
+            tools:text="Tag" />
+
+        <View
+            android:layout_width="match_parent"
+            android:layout_height="1dp"
+            android:layout_marginStart="@dimen/spacing_xlarge"
+            android:layout_marginTop="@dimen/spacing_medium"
+            android:layout_marginEnd="@dimen/spacing_xlarge"
+            android:layout_marginBottom="@dimen/spacing_medium"
+            android:background="@color/grey_10" />
+
+        <androidx.appcompat.widget.AppCompatTextView
+            android:id="@+id/description_text_view"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:textAppearance="@style/TextAppearance.MaterialComponents.Subtitle2"
+            tools:text="Description" />
+    </LinearLayout>
+</com.google.android.material.card.MaterialCardView>
diff --git a/app/src/main/res/values-fa/strings.xml b/app/src/main/res/values-fa/strings.xml
index 0a83849..66f15c4 100644
--- a/app/src/main/res/values-fa/strings.xml
+++ b/app/src/main/res/values-fa/strings.xml
@@ -5,7 +5,7 @@
     <string name="password_label">رمزعبور</string>
     <string name="new_user_label">کاربر جدید؟</string>
     <string name="sign_up_label">ثبت‌نام</string>
-    <string name="sentence_label">جمله:</string>
+    <string name="sentence_label">جمله</string>
     <string name="next_sentence_label">جمله بعدی</string>
     <string name="select_word_tag_label">انتخاب برچسب</string>
     <string name="settings_label">تنظیمات</string>
@@ -32,4 +32,6 @@
     <string name="duplicate_email_message">ایمیل وارد شده قبلا ثبت‌نام کرده است</string>
     <string name="sign_out_layout">خروج از حساب‌کاربری</string>
     <string name="token_invalid_message">توکن نامعتبر است. لطفا این خطا را به ما اطلاع دهید</string>
+    <string name="tag_legend_label">راهنمای تگ‌ها</string>
+    <string name="legend_label">راهنما</string>
 </resources>
diff --git a/app/src/main/res/values/strings.xml b/app/src/main/res/values/strings.xml
index bb18403..a1d0e5b 100644
--- a/app/src/main/res/values/strings.xml
+++ b/app/src/main/res/values/strings.xml
@@ -5,7 +5,7 @@
     <string name="password_label">Password</string>
     <string name="new_user_label">New user?</string>
     <string name="sign_up_label">Sign Up</string>
-    <string name="sentence_label">Sentence:</string>
+    <string name="sentence_label">Sentence</string>
     <string name="next_sentence_label">Next Sentence</string>
     <string name="select_word_tag_label">Select word tag</string>
     <string name="settings_label">Settings</string>
@@ -33,4 +33,6 @@
     <string name="duplicate_email_message">This email is duplicate</string>
     <string name="sign_out_layout">Sign Out</string>
     <string name="token_invalid_message">Token is invalid. please contact administrator</string>
+    <string name="tag_legend_label">Tags Legend</string>
+    <string name="legend_label">Legend</string>
 </resources>
diff --git a/build.gradle b/build.gradle
index d6204d9..d73f688 100644
--- a/build.gradle
+++ b/build.gradle
@@ -9,7 +9,7 @@ buildscript {
         }
     }
     dependencies {
-        classpath 'com.android.tools.build:gradle:3.4.0-alpha10'
+        classpath 'com.android.tools.build:gradle:3.5.0-alpha02'
         classpath "io.objectbox:objectbox-gradle-plugin:2.2.0"
         classpath 'com.google.gms:google-services:4.2.0'
         classpath 'io.fabric.tools:gradle:1.27.0'
diff --git a/gradle/wrapper/gradle-wrapper.properties b/gradle/wrapper/gradle-wrapper.properties
index 3fe316e..34d378f 100644
--- a/gradle/wrapper/gradle-wrapper.properties
+++ b/gradle/wrapper/gradle-wrapper.properties
@@ -1,6 +1,6 @@
-#Mon Dec 31 15:53:53 IRST 2018
+#Sun Jan 27 14:30:30 IRST 2019
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-5.1-milestone-1-all.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-5.1.1-all.zip