Main Page | See live article | Alphabetical index This is not an article about numeral systems. The symbols "12", "twelve", and "XII" are three different numerals, but they represent the same number rather than three different numbers. That is the difference between a numeral and a number. Examples of number systems are: the real numbers, the rational numbers, the algebraic numbers, the complex numbers, the p-adic numbers, the surreal numbers, the hyperreal numbers. Whether, for example, the quaternions should be considered to comprise a number system is perhaps only a matter of convention. This is a stub article. This article is from Wikipedia. All text is available under the terms of the GNU Free Documentation License.