These are illustrations for games, animation, fantasy and other similar projects. The essence of concept art is that the artist embodies several interpretations (concepts) of an object and develops them.
Artists sketch and then add volume, color and space. The sketching of elements can be very detailed and painterly, and sometimes the idea is more important than the technique.
Objects for rendering can be objects – character, surroundings, artifacts, scenes. And their interaction reveals characters and states.
Authors who are skilled at modeling in 3D can and do create entire worlds, which then come to life through the efforts of many people. For example, the Star Wars saga is the result of the work of dozens of artists. Comics and manga can also be considered concept art, as the coolest graphic novels eventually become animated.
Drawing can be used to recreate a story with precise detail and make any fiction believable and existent. A skilled artist creates the illusion of dynamics and depth on a flat and still sheet.
Animation is a rather time-consuming skill to learn, but the result is worth all the expense. Objects and backgrounds come into motion after sketching (they are called animatik). This kind of sketch for sequential scenes is also used for photo and video.