At every point in time, a boolean signal is either true or false. For example, your mouth is either open or closed. It can't be both at the same time and it is always one or the other.
A pulse is an event that occurs at some point in time. It could happen multiple times, but it's a discrete event, as opposed to a boolean signal, which is continuous. For example, a head shake or a head nod.
A point is a three-dimensional signal that can represent a rotation or scale or position.
A scalar is a one-dimensional, continuous value that changes over time. For example, how open your mouth is.
Progress is a scalar signal that's restricted to the 0-1 range. It could be used to drive an animation.
This data type represents objects like face trackers and scene objects.