I don't know much about art history or different drawing traditions, but I often see this style of line art (done in pen and ink I think?) which uses many thin lines for shading. Some examples of what I'm talking about include:
I never know how to describe this style of drawing and search for more examples. I'm also not sure if there's a term for this style of art, or if I'm grouping together unrelated art styles, but any help would be greatly appreciated!