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 King's Crown quilt block gives you chances to practice your skills on a variety of patches. The centre of this block is made with a square in a square patch. This could be the perfect spot to utilize a "fussy cut" square showing a specific motif, or as is shown here -- a simple plain patch where you can feature an interesting quilting design.
The other patches used are frequently seen in a wide variety of quilt blocks -- the half square triangle, the quarter square triangle, and my favourite patch -- the flying geese unit.
The two sample quilts illustrated both feature lots of free space to showcase your quilting designs. The sky is the limit!