2D design is flat design, like drawing or sketching.
http://resources.hwb.wales.gov.uk/VTC/ngfl/dandt/75/Tutorials/2D%20Design/Section1.pdf
use this pdf to learn how to use it
Answer:
In relief printing, the artist draws a design on a smooth block of material—usually wood or linoleum—and uses tools to carefully cut away the areas that are not to be printed, leaving behind a raised surface of lines and shapes.
If it's on a house post, I'm sure it's signifying that Yoruba will offer hospitality
