A simple square has endless potential. The Sweaters Introduction page shows some garments that can be made with the most basic squares, progressing to designs in two colours, diagonally striped squares and other variations.
These are our favourite kinds of squares. If you want precise instructions for making them and lots of ideas for creating designs with them, we have free patterns on the Squares for Afghans page.
Instructions are also included in the Woolly Thoughts book, along with many other ideas for designing garments.
This jacket uses a slightly different square where one half is knit at right angles to the other.
(This is not included in Woolly Thoughts book but would be fairly easy to create from the instructions for other shapes.)
The square was adapted to make a matching hat and fingerless mittens.