Traditionally the Corner to Corner (C2C) Box Stitch is made with double crochet, but it can also be made with half double crochet to make the squares smaller. C2C has become a hot stitch over the past few years. It can be used to make a square or rectangle of any size with pretty much any yarn. Plus it is made of blocks so it can be used to create graphed images, and if made with half double crochet the boxes are a little smaller so a graph with more squares can be used. Once you have this stitch down you can take a graphed image (such as a cross stitch pattern) and crochet it. So cool!!
Get the free crochet pattern here: https://jessieathome.com/half-double-crochet-c2c/