Classic video game systems like the NES were made at a time when television sets were very different than they are now. If you're playing a modern console like the PS4, Xbox One, or Nintendo Switch on a TV, you're probably gaming in a 16:9 aspect ratio, or something close to it depending on the size of your screen. These days, TV screens are relatively wide, but back in the '80s, they were more like boxes. That's why NES games have an aspect ratio of 8:7, which is essentially a square. As a result, they look kind of weird on modern screens. But now there's an NES emulator that has a creative solution to that problem, allowing players to see more of the vintage games they're playing (via BoingBoing).
"As players move within a level, wideNES records the screen, gradually building-up a map of what’s been explored. On subsequent playthroughs of the level, wideNES syncs the action on-screen to the generated map, effectively letting players see more of the level by “peeking” past the edge of the NES’s screen!"
Featured image: Nintendo