What is Android Relative Layout?

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:paddingLeft="15dp"
    android:paddingRight="15dp"
    android:background="@color/purple_200">
    <TextView
        android:id="@+id/textview1"
        android:layout_width="352dp"
        android:layout_height="50dp"
        android:text=" Do you want to go out to eat? "
        android:textColor="#070707"
        android:textSize="20sp" />
    <Button
        android:id="@+id/button1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignBottom="@id/textview1"
        android:layout_marginBottom="-90dp"
        android:text="Okay" />
    <Button
        android:id="@+id/b2"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignRight="@id/button1"
        android:layout_alignBottom="@id/textview1"
        android:layout_marginRight="-225dp"
        android:layout_marginBottom="-90dp"
        android:text="No" />
    <TextView
        android:id="@+id/text2"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignBottom="@+id/button1"
        android:layout_centerInParent="true"
        android:textColor="#070707"
        android:textSize="20dp"
        android:layout_marginBottom="-200dp"
        android:text="That's it" />
</RelativeLayout>