wpf what are grids used for code example

Example 1: wpf grid

<Window x:Class="WpfTutorialSamples.Panels.TabularGrid"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        Title="TabularGrid" Height="300" Width="300">
    <Grid>
		<Grid.ColumnDefinitions>
			<ColumnDefinition Width="2*" />
			<ColumnDefinition Width="1*" />
			<ColumnDefinition Width="1*" />
		</Grid.ColumnDefinitions>
		<Grid.RowDefinitions>
			<RowDefinition Height="2*" />
			<RowDefinition Height="1*" />
			<RowDefinition Height="1*" />
		</Grid.RowDefinitions>
	</Grid>
</Window>

Example 2: wpf grid

<Window x:Class="WpfTutorialSamples.Panels.TabularGrid"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        Title="TabularGrid" Height="300" Width="300">
    <Grid>
		<Grid.ColumnDefinitions>
			<ColumnDefinition Width="2*" />
			<ColumnDefinition Width="1*" />
			<ColumnDefinition Width="1*" />
		</Grid.ColumnDefinitions>
		<Grid.RowDefinitions>
			<RowDefinition Height="2*" />
			<RowDefinition Height="1*" />
			<RowDefinition Height="1*" />
		</Grid.RowDefinitions>
		<Button>Button 1</Button>
		<Button Grid.Column="1">Button 2</Button>
		<Button Grid.Column="2">Button 3</Button>
		<Button Grid.Row="1">Button 4</Button>
		<Button Grid.Column="1" Grid.Row="1">Button 5</Button>
		<Button Grid.Column="2" Grid.Row="1">Button 6</Button>
		<Button Grid.Row="2">Button 7</Button>
		<Button Grid.Column="1" Grid.Row="2">Button 8</Button>
		<Button Grid.Column="2" Grid.Row="2">Button 9</Button>
	</Grid>
</Window>