Happy 118th birthday to special relativity!
Albert Einstein introduced special relativity in the paper "On The Electrodynamics Of Moving Bodies," published #OTD in 1905 in the journal Annalen der Physik.
Manuscript: https://onlinelibrary.wiley.com/doi/abs/10.1002/andp.19053221004
English Translation: https://www.fourmilab.ch/etexts/einstein/specrel/www/