Grid system
From 1 to 12 columns
Default and probably the most used grid system is this. It offers 12 grid columns, from 1 to 12 and allows to combine them in many ways. It is fully responsive and use percentages not pixels. This is what make it always to stay full width.
From 1 to 12 columns + column halves
Sometimes you may need a grid column that is a bit wider than one and a bit narrow than the next possible column. Here you can use halves. For example if you want to use a column that is between 7 & 8, that would be 3.5 and the CSS class is .desk-7-5. Simple like that. Now to complete the row you may use .desk-4-5 and this will result in a total number 12.
Column X of Y total columns, possible in a row.
What if you know the number of columns you want to use and nothing more, just columns? For this is better to say column X of Y in total. For example to create 5 columns it's not possible with the grid system demonstrated above, but with the next below you can create any number of equal columns. Here you can use this class .desk-1of5 and it will create 5 equal columns.