There are a ton of small tricks that are often overlooked in Illustrator (and all of the Adobe Suite) and this is just a quick one that makes life easier especially for things like icon design. Using the Direct Selection Tool, you can choose any number of single points and use the align panel to get them in the exact place. It’s much quicker than clicking and dragging hoping that the smart guides will make it snap perfectly (which a lot of times I find doesn’t work until you fiddle around a bit).