Use the layout directive on a container element to specify the layout direction for its children: horizontally in a row (layout="row") or vertically in a column (layout="column"). Note that row is the default layout direction if you specify the layout directive without a value.

row Items arranged horizontally. max-height = 100% and max-width is the width of the items in the container.
column  Items arranged vertically. max-width = 100% and max-height is the height of the items in the container.