Allow keyframes between frames
Hello,
I am following one tutorial where am learning about keyframes and graphs. There the tutor added a keyframe between two keyframes and then he said we can do this because of ''allow keyframes between frames" option is checked. But I don't understand this. I googled, but no specific discussion about this particular option. It's in the 'Choose graph type and options- 'allow keyframes between frames". I don't understand what is the use of it. I uncheck it and I can add a keyframe in the graph using a pen tool, I check it, and still, I can add keyframes using the pen tool. So what does it do?
What's the specialty of having this on and off? is it important?
Thank you.

