diff --git a/app/src/main/AndroidManifest.xml b/app/src/main/AndroidManifest.xml
index 4826623..d798f22 100644
--- a/app/src/main/AndroidManifest.xml
+++ b/app/src/main/AndroidManifest.xml
@@ -16,7 +16,7 @@
         android:usesCleartextTraffic="true"
         tools:targetApi="31">
         <activity
-            android:name=".MainActivity"
+            android:name=".presentation.main.MainActivity"
             android:screenOrientation="portrait"
             android:exported="true">
             <intent-filter>
diff --git a/app/src/main/java/com/release/keyneez/MainActivity.kt b/app/src/main/java/com/release/keyneez/presentation/main/MainActivity.kt
similarity index 85%
rename from app/src/main/java/com/release/keyneez/MainActivity.kt
rename to app/src/main/java/com/release/keyneez/presentation/main/MainActivity.kt
index 10fa87f..627610f 100644
--- a/app/src/main/java/com/release/keyneez/MainActivity.kt
+++ b/app/src/main/java/com/release/keyneez/presentation/main/MainActivity.kt
@@ -1,8 +1,9 @@
-package com.release.keyneez
+package com.release.keyneez.presentation.main
 
 import android.os.Bundle
 import androidx.appcompat.app.AppCompatActivity
 import com.kakao.sdk.common.util.Utility
+import com.release.keyneez.R
 import timber.log.Timber
 
 class MainActivity : AppCompatActivity() {
diff --git a/app/src/main/java/com/release/keyneez/util/DiffCallback.kt b/app/src/main/java/com/release/keyneez/util/DiffCallback.kt
new file mode 100644
index 0000000..2a7d780
--- /dev/null
+++ b/app/src/main/java/com/release/keyneez/util/DiffCallback.kt
@@ -0,0 +1,14 @@
+package com.release.keyneez.util
+
+import androidx.recyclerview.widget.DiffUtil
+
+class DiffCallback<T : Any>(
+    val onItemsTheSame: (T, T) -> Boolean,
+    val onContentsTheSame: (T, T) -> Boolean
+) : DiffUtil.ItemCallback<T>() {
+    override fun areItemsTheSame(oldItem: T, newItem: T): Boolean =
+        onItemsTheSame(oldItem, newItem)
+
+    override fun areContentsTheSame(oldItem: T, newItem: T): Boolean =
+        onContentsTheSame(oldItem, newItem)
+}
diff --git a/app/src/main/java/com/release/keyneez/util/OnSingleClickListener.kt b/app/src/main/java/com/release/keyneez/util/OnSingleClickListener.kt
new file mode 100644
index 0000000..d089d47
--- /dev/null
+++ b/app/src/main/java/com/release/keyneez/util/OnSingleClickListener.kt
@@ -0,0 +1,21 @@
+package com.release.keyneez.util
+
+import android.os.SystemClock
+import android.view.View
+
+class OnSingleClickListener(
+    private var interval: Int = 600,
+    private var onSingleClick: (View) -> Unit
+) : View.OnClickListener {
+
+    private var lastClickTime: Long = 0
+
+    override fun onClick(v: View) {
+        val elapsedRealtime = SystemClock.elapsedRealtime()
+        if ((elapsedRealtime - lastClickTime) < interval) {
+            return
+        }
+        lastClickTime = elapsedRealtime
+        onSingleClick(v)
+    }
+}
diff --git a/app/src/main/java/com/release/keyneez/util/UiState.kt b/app/src/main/java/com/release/keyneez/util/UiState.kt
new file mode 100644
index 0000000..e6db0b7
--- /dev/null
+++ b/app/src/main/java/com/release/keyneez/util/UiState.kt
@@ -0,0 +1,7 @@
+package com.release.keyneez.util
+
+sealed class UiState {
+    object Success : UiState()
+    data class Failure(val code: Int?) : UiState()
+    object Error : UiState()
+}
diff --git a/app/src/main/java/com/release/keyneez/util/binding/BindingActivity.kt b/app/src/main/java/com/release/keyneez/util/binding/BindingActivity.kt
new file mode 100644
index 0000000..c792623
--- /dev/null
+++ b/app/src/main/java/com/release/keyneez/util/binding/BindingActivity.kt
@@ -0,0 +1,19 @@
+package com.release.keyneez.util.binding
+
+import android.os.Bundle
+import androidx.annotation.LayoutRes
+import androidx.appcompat.app.AppCompatActivity
+import androidx.databinding.DataBindingUtil
+import androidx.databinding.ViewDataBinding
+
+abstract class BindingActivity<T : ViewDataBinding>(
+    @LayoutRes private val layoutRes: Int
+) : AppCompatActivity() {
+    protected lateinit var binding: T
+
+    override fun onCreate(savedInstanceState: Bundle?) {
+        super.onCreate(savedInstanceState)
+        binding = DataBindingUtil.setContentView(this, layoutRes)
+        binding.lifecycleOwner = this
+    }
+}
diff --git a/app/src/main/java/com/release/keyneez/util/binding/BindingFragment.kt b/app/src/main/java/com/release/keyneez/util/binding/BindingFragment.kt
new file mode 100644
index 0000000..143b4f9
--- /dev/null
+++ b/app/src/main/java/com/release/keyneez/util/binding/BindingFragment.kt
@@ -0,0 +1,33 @@
+package com.release.keyneez.util.binding
+
+import android.os.Bundle
+import android.view.LayoutInflater
+import android.view.View
+import android.view.ViewGroup
+import androidx.annotation.LayoutRes
+import androidx.databinding.DataBindingUtil
+import androidx.databinding.ViewDataBinding
+import androidx.fragment.app.Fragment
+import com.release.keyneez.R
+
+abstract class BindingFragment<T : ViewDataBinding>(
+    @LayoutRes private val layoutRes: Int
+) : Fragment() {
+    private var _binding: T? = null
+    protected val binding get() = _binding ?: error(getString(R.string.binding_error))
+
+    override fun onCreateView(
+        inflater: LayoutInflater,
+        container: ViewGroup?,
+        savedInstanceState: Bundle?
+    ): View? {
+        _binding = DataBindingUtil.inflate(inflater, layoutRes, container, false)
+        binding.lifecycleOwner = viewLifecycleOwner
+        return binding.root
+    }
+
+    override fun onDestroyView() {
+        super.onDestroyView()
+        _binding = null
+    }
+}
diff --git a/app/src/main/java/com/release/keyneez/util/extension/ActivityExt.kt b/app/src/main/java/com/release/keyneez/util/extension/ActivityExt.kt
new file mode 100644
index 0000000..c8c74f2
--- /dev/null
+++ b/app/src/main/java/com/release/keyneez/util/extension/ActivityExt.kt
@@ -0,0 +1,9 @@
+package com.release.keyneez.util.extension
+
+import android.app.Activity
+import android.view.View
+
+/** hide keyboard from activity window */
+fun Activity.hideKeyboard() {
+    hideKeyboard(currentFocus ?: View(this))
+}
diff --git a/app/src/main/java/com/release/keyneez/util/extension/ContextExt.kt b/app/src/main/java/com/release/keyneez/util/extension/ContextExt.kt
new file mode 100644
index 0000000..573efce
--- /dev/null
+++ b/app/src/main/java/com/release/keyneez/util/extension/ContextExt.kt
@@ -0,0 +1,29 @@
+package com.release.keyneez.util.extension
+
+import android.app.Activity
+import android.content.Context
+import android.view.View
+import android.view.inputmethod.InputMethodManager
+import android.widget.Toast
+import com.google.android.material.snackbar.Snackbar
+
+/** hide keyboard from window */
+fun Context.hideKeyboard(view: View) {
+    val inputMethodManager = getSystemService(Activity.INPUT_METHOD_SERVICE) as InputMethodManager
+    inputMethodManager.hideSoftInputFromWindow(view.windowToken, 0)
+}
+
+/** Make a Snackbar to display a message for 1.5 seconds */
+fun Context.showSnackbar(view: View, msg: String) {
+    Snackbar.make(view, msg, Toast.LENGTH_SHORT).show()
+}
+
+/** Make a Toast to display a message for 1.5 seconds */
+fun Context.showToast(msg: String) {
+    Toast.makeText(this, msg, Toast.LENGTH_SHORT).show()
+}
+
+fun Context.dpToPx(dp: Int): Int {
+    val scale = resources.displayMetrics.density
+    return (dp * scale).toInt()
+}
diff --git a/app/src/main/java/com/release/keyneez/util/extension/MutableLiveDataExt.kt b/app/src/main/java/com/release/keyneez/util/extension/MutableLiveDataExt.kt
new file mode 100644
index 0000000..1de3ffb
--- /dev/null
+++ b/app/src/main/java/com/release/keyneez/util/extension/MutableLiveDataExt.kt
@@ -0,0 +1,7 @@
+package com.release.keyneez.util.extension
+
+import androidx.lifecycle.MutableLiveData
+
+fun <T> MutableLiveData<T>.notifyObserver() {
+    this.value = this.value
+}
diff --git a/app/src/main/java/com/release/keyneez/util/extension/ViewExt.kt b/app/src/main/java/com/release/keyneez/util/extension/ViewExt.kt
new file mode 100644
index 0000000..70fc8c1
--- /dev/null
+++ b/app/src/main/java/com/release/keyneez/util/extension/ViewExt.kt
@@ -0,0 +1,15 @@
+package com.release.keyneez.util.extension
+
+import android.view.View
+import com.google.android.material.snackbar.Snackbar
+import com.release.keyneez.util.OnSingleClickListener
+
+/** Register a callback to be invoked when this view is clicked. If this view was clicked within 1 second, the callback will not be invoked. */
+fun View.setOnSingleClickListener(onSingleClick: (View) -> Unit) {
+    setOnClickListener(OnSingleClickListener { onSingleClick(it) })
+}
+
+/** Make a Snackbar to display a message for 1.5 seconds */
+fun View.showSnackbar(message: String) {
+    Snackbar.make(this, message, Snackbar.LENGTH_SHORT).show()
+}
diff --git a/app/src/main/res/layout/activity_main.xml b/app/src/main/res/layout/activity_main.xml
index 17eab17..435ca35 100644
--- a/app/src/main/res/layout/activity_main.xml
+++ b/app/src/main/res/layout/activity_main.xml
@@ -4,7 +4,7 @@
     xmlns:tools="http://schemas.android.com/tools"
     android:layout_width="match_parent"
     android:layout_height="match_parent"
-    tools:context=".MainActivity">
+    tools:context=".presentation.main.MainActivity">
 
     <TextView
         android:layout_width="wrap_content"
diff --git a/app/src/main/res/values/strings.xml b/app/src/main/res/values/strings.xml
index f0a9551..049a768 100644
--- a/app/src/main/res/values/strings.xml
+++ b/app/src/main/res/values/strings.xml
@@ -1,6 +1,9 @@
 <resources>
     <string name="app_name">Keyneez</string>
 
+    // common
+    <string name="binding_error">Binding not initialized to reference the view.</string>
+
     // search
     <string name="search_content">제목, 키워드</string>
     <string name="search_result">검색결과</string>