\begin{definition}[Definition:Formal Language]
A '''formal language''' is a structure $\LL$ which comprises:
:A set of symbols $\AA$ called the alphabet of $\LL$
:A collation system with the unique readability property for $\AA$
:A formal grammar that determines which collations belong to the formal language and which do not.
Often, the collation system is left implicit, and taken simply to match the formal grammar.
\end{definition}