Blend spaces vs blend nodes

Hi

I was wondering…what exactly is the difference between blend spaces and blend nodes? When should I use blend spaces and when blend nodes?

thanks in advance.

Blend Space tutorial: - YouTube

Blend Spaces blend your animation based on some variables, like explained in the video BlendSpace1D blends animations based on 1 variable, so you could mix in several animations or just 2 for thing like idle/walk.
Blend Nodes, for example in Animation Blueprint there is a Blend Per Bone Node, are used more like for overriding animation on specific bones , you could also override it on as many bones as you’d like so you have a much better control compared to Blend Spaces way of doing it, but Blend Space will do a better job at blending full body animations.

More reading: Can I have a skeletal mesh play 2 animations at the same time? - Character & Animation - Unreal Engine Forums

Thanks! very useful