per cambridge, plate means
a flat piece of something that is hard and does not bend
so, when talking about brick wall, plate layout means a flat piece of bricks, shown like the following image (img_1), is my understanding right?
similarly, when talking about stud wall, plate layout means a flat piece of studs, the whole thing pointed out by red circle (img_2), is my understanding right?
However, in img_2, it seems that head plate and sole plate refer to something like a beam.
this post says
Start by aligning your top and bottom plate ends flush together and measure 15 1/4 inches to side of first stud placement. Each corresponding measurement should be 3/4 of an inch shy of stud marks on your tape measure. This will give you studs that are on 16 inch center layouts. Check out the video above to see this process in action.
Is the bottom plate end refer to the sole plate in img_2?