The Tenth Dimension is based on the idea that countless tiny "Superstrings" are vibrating in a tenth dimension. In order to begin to understand this theory, we have to first comprehensively question our notion of infinity, the plausible and implausible, and consciousness itself.
Welcome to a world you've never imagined.
What I'm about to tell you will probably hurt your brain, as it hurt mine. The brains that are hurting the most are probably the ones that came up with this shit in the first place. It's difficult to comprehend that everything that you have ever experienced has in some small but significant way been an illusion.
Why is this? Because everything you have ever experienced, you have understood as happening in three dimensions of space – up-down, left-right, and front-back. Yet this is not how things happen. Things happen in more than three dimensions; to accept our understanding of a world as the only dimension is to capitulate to a game that the universe is persistently playing on us.
When someone sparks up a casual conversation regarding "different dimensions," our brain will automatically imagine something like parallel universes or realities much like our own, but where things possibly happened or worked out differently. While understanding the roles that different dimensions play in the universe can be quite a headache, you simply need to think of them as dimensions with different features, that differ from our comprehension of the terms "real" and "not real."
These different features are what command the entire universe, all of the particles that make up anything, and the fundamental forces of nature. If you were to enter the tenth dimension, you would see that anything in the human mind is imaginable at your fingertips; all possibilities contained.
Unfortunately if you wanted to travel farther than this, everything beyond the tenth dimension is impossible for us mere mortals to perceive. However, the other six dimensions are very important for String Theory to make sense. It's most likely that the remaining six dimensions reside in the form of a Calabi- Yau manifold.
Long story short; we would never be able to actually understand or imagine this either, but the Calabi-Yau in theory would have been the cause and conductor of the beginning of the universe. This is also why scientists use telescopes to look for light from far off to understand the expansion of the cosmos.
To further understand higher dimensions, consider this: In the ocean there are many different types of fish; a shark for example spends their entire lives grazing the big blue. The shark is only vaguely aware of the world beyond. To a shark scientist, the entire universe is only two dimensions, length and width. "Height" or "up" doesn't exist. They wouldn't be able to conjure up the 3rd dimension outside of the sea. But if a storm were to hit above the shark, the surface above would become waves and rippled. Even though they wouldn't grasp that it is indeed the third dimension they're gazing at they would clearly see the warped water on the surface. So it goes for us humans, even though we can't see the higher dimensions; we CAN see the waves as they vibrate.
In fact, "light" is theoretically nothing but vibrations wrinkling along the fifth dimension... Just a thought.