# Blackboard bold

Blackboard bold is probably the most common way of denoting the "standard" number sets: the natural numbers, the integers and so on. In AMS-LaTeX, you use the `\mathbb{...}` command to obtain them; the ConTeXt way is the `\blackboard{...}` command. Also, the following commands are defined:

```\naturalnumbers
\integers
\rationals
\reals
\complexes,
\primes

\blackboard{F}
\blackboard{O}
```