  This article is a short and elementary introduction to the monstrous
moonshine aiming to be as accessible as possible. I first review the
classification of finite simple groups out of which the monster naturally
arises, and features of the latter that are needed in order to state the
moonshine conjecture of Conway and Norton. Then I motivate modular functions
and modular forms from the classification of complex tori, with the definitions
of the J-invariant and its q-expansion as a goal. I eventually provide evidence
for the monstrous moonshine correspondence, state the conjecture, and then
present the ideas that led to its proof. Lastly I give a brief account of some
recent developments and current research directions in the field.
