The sutras often use the word 'great void' to explain the significance of sunyata. In general, we understand the 'great void' as something that contains absolutely nothing. However, from a Buddhist perspective, the nature of the 'great void' implies something which does not obstruct other things, in which all matters perform their own functions. Materials are form, which by their nature, imply obstruction. The special characteristic of the 'great void' is non-obstruction. The 'great void' therefore, does not serve as an obstacle to them. Since the 'great void' exhibits no obstructive tendencies, it serves as the foundation for matter to function. In other words, if there was no 'great void' nor characteristic of non-obstruction, it would be impossible for the material world to exist and function.