There are two common uses of Zero: One use is as a empty place indicator in our place-value number system. Hence in a number like 2106 the zero is used so that the positions of the 2 and 1 are correct. Clearly 216 means something quite different. The second use of zero is as a number itself in the form we use it as 0. There are also different aspects of zero within these two uses, namely the concept, the notation, and the name.

This category is concerned with the second use, the number zero itself. It lists sites that discuss the history, use and specialities of the number zero.

Additionally such topics as "division by zero" are listed.
Please just submit sites discussing the number zero in this category. For other special numbers, please use either one of the other subcategories or the main category for specific numbers.