I thought I understood pressure in fluids, but it seems like its starting to make less sense to me. Let's consider a flow through a pipe where the rho g h term drops out. Therefore, we would only have the dynamic and static pressure. This is where I start to lose it. I have been told that when the flow of water goes from a wider section of a pipe to skinnier one. the dynamic pressure increases and static pressure decreases. The dynamic pressure going up makes sense, but I don't understand why the static pressure goes down. I think it may be that I don't understand exactly what static pressure is. Does the static pressure act equally in all three dimensional directions or does it act only horizontally and vertically? Does it act on the pipes pressing outward or does it act horizontally pressing the fluid forward? I don't understand why the pressure wouldn't increase if the fluid is moving faster because i think getting hit by something fast would hurt more than getting hit by something slow. Could someone please give a good basic description of what it is and how it changes because I can't find any simple answers. I would really appreciate it!