"Pencil sketches" refers to drawings made using a pencil. These are simple and basic drawings that are created with a pencil, without any colors or additional details. Full definition
Those games in particular actually train the user to get used to insane levels of violence and gore, this game has a few delightful pencil sketches of some cute babies. (gigaom.com)
He'll talk about publishing work as a young artist, and reveal his process from pencil sketches to finished artwork. (fadmagazine.com)
Inside his studio, brightly colored pencil sketches and small pizza box - sized paintings line the walls. (ffffffwalls.com)