android:background vs android:drawableLeft/drawableTop/drawableRight/drawableBottom

android:background specify drawable to use as the background.

android:drawableLeft/drawableTop/drawableRight/drawableBottom specify the drawable to be drawn to the left/top/right/bottom.

Here is some examples using android:background and android:drawableLeft/drawableTop/drawableRight/drawableBottom.

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    >
<TextView  
    android:layout_width="fill_parent" 
    android:layout_height="wrap_content" 
    android:text="@string/hello"
    />
<Button  
    android:layout_width="wrap_content" 
    android:layout_height="wrap_content" 
    android:background="@drawable/icon"
    android:text="Button with background"
    />
<EditText
    android:layout_width="fill_parent"
    android:layout_height="wrap_content" 
    android:background="@drawable/icon"
    android:text="EditText with background"
    />
<CheckBox
    android:layout_width="fill_parent"
    android:layout_height="wrap_content" 
    android:background="@drawable/icon"
    android:text="CheckBox with background"
    />
<Button  
    android:layout_width="wrap_content" 
    android:layout_height="wrap_content" 
    android:drawableLeft="@drawable/icon"
    android:text="Button with drawableLeft"
    />
<EditText
    android:layout_width="fill_parent"
    android:layout_height="wrap_content" 
    android:drawableLeft="@drawable/icon"
    android:text="EditText with android:drawableLeft"
    />
<CheckBox
    android:layout_width="fill_parent"
    android:layout_height="wrap_content" 
    android:drawableLeft="@drawable/icon"
    android:text="CheckBox with android:drawableLeft"
    />
</LinearLayout>