Wall
A wall is a very simple tile. It simply obstructs the path of anything.
Heights
Walls can come in various heights. The height of a wall doesn't affect the gameplay but can be used to make a level look better. A height of a wall is determined by a number with a decimal place. (e.g. A 1.0 wall is twice as high as a 0.5 wall) In The Original Wonderland, there is only one height of a wall, the 1.0 wall. In Return To Wonderland Deluxe/Platinum and Wonderland Secret Worlds, other heights exist such as 1.5 and 2.0 walls. In the Wonderland Adventures series, Walls can go from -5.0 to 5.0 (with a negative value making a pit rather than a wall) in increments and decrements of 0.1.
Fake Walls
A fake wall is a tile which has the appearance of a wall, but is actually a floor. There is also a tile which is the opposite: It looks like a floor, but is actually a wall. Fake walls usually have a slightly different appearance from normal walls, e.g. lighter, darker, more contrast, or have a decoration or doorway drawn on them. In addition to their official name, fake walls, they are also known as secret walls or weak walls.