\begin{definition}[Definition:Set/Explicit Set Definition]
A (finite) set can be defined by '''explicitly''' specifying ''all'' of its elements between the famous curly brackets, known as '''set braces''': $\set {}$.
When a set is defined like this, note that ''all'' and ''only'' the elements in it are listed.
This is called '''explicit (set) definition'''.
It is possible for a set to contain other sets. For example:
:$S = \set {a, \set a}$
\end{definition}