The hbox component is used to create a horizontally oriented box. Each component placed in the hbox will be placed horizontally in a row.

    <zk>
    <vbox>    
        <button label="Button 1"/>        
        <button label="Button 2"/>        
    </vbox>    
    <hbox>    
        <button label="Button 3"/>        
        <button label="Button 4"/>        
    </hbox>    
</zk>