Equal Curvature Vs Tangent Face

[Maha Nadarasa]

What is the different between these two?

[Lucas]

Equal Curvature is useful when you are connecting a spline to other sketch entity, creates a better curvature in the connecting point for a smoother transition (check curvature combs)

Tangent Face will apply a relation with the face. As the name says, will be tangent lol

Andrew Lowe and DiMonte Group have a lot of videos explaining it, its pretty useful for surfacing.