For most servers, this can count as cheating because you can see the surroundings for mobs, loot chests or precious ores. Make sure that you're allowed to use this glitch in servers, though. If you are in the Nether, you can use x-ray glitches to locate fortresses and bastions.

They can also help you find end portal rooms once you are near a stronghold. X-ray glitches are useful for locating underground structures such as dungeons and mineshafts.