For me, once I decided to get into half-square triangles, I saw a pattern (it was not free) that I liked and thought that I could do it on my own without the pattern directions. The only problem I encountered was trying to figure out what size to make the HST's so that they would be the same size as the 4" squares. loll. Since I am rather new to quilting, these charts are a big help. The basic stuff I can figure out for myself... but why have to, when all I need to do is just look at the charts now. lolll. It does save time on the math when you are trying to figure out how much fabric you need to make a quilt when you do not have a pattern. Since I do not have much of a Stash, it really does help me out a lot.