A void cube is just like a normal rubik's cube except it has no centre pieces just holes that you can look through. This puzzle invented by Katsuhiko Okamoto has the same number of possible permutations as a normal cube but it is more difficult to solve because it loses a level of visibility. Its not as smooth to turn and doesn't cut corners as well but it is still a very fun puzzle to try and you can even simulate one by peeling off all the center stickers from a regular rubik's cube.
To solve a void cube you will need to understand how the cube works and use the same algorithms that you would with a normal rubik's cube. The only difference is that you may run into parities because of the missing centers. This is because the centres on a cube determine the colour of each face. If you solve a face around the wrong centre it can create an odd parity, and if this happens on a void cube it can be very hard to figure out how to fix the situation.
To solve a void cube, first identify the non-white part of any edge piece (an edge is made up of two colours so if it has a white and a different coloured non-white part then this is the edge you need to focus on). Then match that edge's non-white part to its centre using hit and trial. Once you have matched the centre of this edge to the correct colour then apply the same algorithms as you would with a normal cube until it is solved.