The grid is an invisible structure that collects all the elements within a web page together. Grids are never properly visible, however traces of the grids’ “discipline” can be seen by the placement of elements within a web page. The grid also dictates the size of such design elements as widths of column texts, repeated placement of elements, padding around imagery, word spacing, line height, etc. A grid’s main goal is to create a connection of unity within a design, which in turn makes web page content flow better, producing a more readable and enjoyable web page design.
However, the benefits of a grid on a particular design will only take effect if the grid is used at the initial stages of the design process. Attempting to implement a grid into an existing design will not create the same fluid layout or unity of content.