Why do these forums have both "Like" and "Helpful" buttons?

As the title says. These are primarily support forums, so overwhelmingly any time I like a post, it's because I found it to be helpful. But I assume Adobe had Very Good Reasons for implementing these two seemingly-redundant buttons, so whenever it does occur to me to use them, I worry that I'm using them wrong. Since I dislike both worrying and doing things wrong, as a result I pretty much never use either of them.