Help Me Understand Value Bet vs Semi-Bluff

[Kellon]

Can someone please explain the difference between these two concepts, if there is an actual difference? As I read about them and read various definitions of them, they both seem to be a situation of betting, or raising, when you don't currently have the best hand but have sufficient outs to have a fair chance to improve to the best hand, and thus have the appropriate odds to make the bet profitable in the long run. If there is a significant distinction between the two concepts, I'm missing it. TIA, Kellon