how to remove label from application

i made my first app today using an application named "A.I.D.E". i am an android user and its my first time making an app, how can i remove my app name and lable from the top of the main screen? i named my app "YT Studio" but i dont want to show this name and lable on top of my main screen, i want it to be blank, can someone help me? i gave you my android manifest.xml and main.java file for the reference, i would love to edit my question for more help in future.

android manifest.xml

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.ojhastudios.ytstudio" >

    <application
        android:allowBackup="true"
        android:icon="@drawable/ic_launcher"
        android:label="YT Studio"
        android:theme="@style/AppTheme"
        android:resizeableActivity = "true">
        <activity
            android:name=".MainActivity">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>

</manifest>

main.xml

<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:orientation="vertical"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <TextView
        android:text="@string/hello_world"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="30dp" />

</LinearLayout>

edit: one fellow asked me for code, there you go

package com.mycompany.myapp;

import android.app.*;
import android.os.*;

public class MainActivity extends Activity 
{
    @Override
    protected void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        getSupportActionBar().hide();
    }
}