Marking the semi-anniversary of the Fermilab Muon g&minus\;2 experiment (E989) Run 1 result\, this coll oquium will review the current status of the muon magnetic anomaly\, the i nferred evidence of possible particles outside the Standard Model (SM)\, a nd future prospects in this active research field.

\n\nThe intrinsic magnetic field of a simple object\, s
uch as a compass needle\, is expressed in terms of its magnetic moment. &n
bsp\;The magnetic moment of a point particle\, such as the electron\, is p
redicted by relativistic quantum mechanics to be g = 2\, in convenient&nbs
p\;dimensionless units. \;For the electron\, this prediction fails at
the part-per-thousand level\; the resulting magnetic anomaly\, a_{e = (g &minus\; 2)/2\, is due to the electron&rsquo\;s couplings to virt
ual particles excited in the vacuum.}

Muon\, the electron&rsquo\;s 200 times heavier cousin\, experienc
es far stronger couplings to massive virtual particles\, including possibl
e non-SM exotics. The SM provides a prediction for the muon magnetic anoma
ly a_{µ\;} with sub-ppm precision. Hence\, a comparably preci
se measurement of a_{µ\;} offers a uniquely sensitive test fo
r the presence of non-SM particles in nature. For almost 20 years a tantal
izing discrepancy of &sim\; 3 &ndash\; 4&sigma\; has persisted between the
measurements of a_{µ\;}\, and the SM calculations. The Fermi
lab Muon g&minus\;2 Run 1 result brings a much awaited update to this test
\, with much more to come.