java - No resource identifier found for attribute 'orientaton' in package 'android' activity_main.xml -

i encountered error while debugging "hello world" app found in started android development tutorial. here full activity_main.xml

    <?xml version="1.0" encoding="utf-8"?>     <linearlayout xmlns:android="http://schemas.android.com/apk/res/android"  xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent" android:layout_height="match_parent" android:orientaton="horizontal"> <edittext android:id="@+id/edit_message"     android:layout_weight="1"     android:layout_width="0dp"     android:layout_height="wrap_content"     android:hint="@string/edit_message" /> <button     android:layout_width="wrap_content"     android:layout_height="wrap_content"     android:text="@string/button_send" /> 

i need 1 considering believe keystroke keystroke appears in tutorial.

you misspelled orientation - orientat i on, not orientaton.