There are a variety of more pronounced video effects that are both recently developed or archived from the silent film era. Things like wipes, where one image pushes the other off the screen, or the iris in/out, where the image is focused down to a circle on just one aspect of that image, are meant to be seen and are not used to simply maintain continuity. Each of the more obvious video effects is different and therefore has different connotations, but since they are so obvious they are often used for comic, referential, or artistic meaning.