Square is the most classic tile format there is, used across an enormous range of styles and applications, and it works just as comfortably in a traditional space as it does in a thoroughly contemporary one.
It is worth remembering you are not limited to a standard grid layout: square tiles can be offset, stacked, or turned forty-five degrees to create a diagonal diamond pattern instead. They are also the classic choice for a checkerboard design, where two contrasting tiles are laid together for one of the most enduring looks in tiling. Square remains the easiest starting point for anyone planning a project, since it works with almost any layout, colour, or finish you have in mind, from a simple grid to a bold checkerboard.