This animation video is about the types of grade line usually used in fluid mechanics. You should have better understanding of what pitot tube and pizometer is .
Animation video I recommended to watch first:
What is pitot tube? :-
   • What is pitot tube? 3D Animation ( St...  

Visualizing Bernoulli's principle in terms of height :-    • Visualizing Bernoulli's principle in ...  

Enjoy learning ^^.