The half square triangle unit is probably the most commonly used patch in a quilt block -- well it is second only to the square. It is made simply with two triangles, filling up half the square each -- hence the name. Take a quick look through this website, or in any quilting magazine, and you will start to notice that this half square triangle, regardless of its size, is present in more quilts than not.
Free Quilt Block Pattern
The Arizona quilt block is another interesting geometric block comprised of simple shapes. Using just rectangles, half square triangles and flying geese patches, you can create any number of interesting quilt blocks by simply changing up the number of colours and fabrics used.
The sample quilts illustrated show how very different the end result can be by choosing to set the blocks on point or side-by-side with sashing.