The Brief: "H/T" is a written abbreviation for "hat tip."

DEEP DIVE
“h/t” stands for “hat tip.” The abbreviation is commonly used on Twitter and other online platforms to give credit to an original source. “H/T” can be used to thank someone for inspiration, ideas, or for bringing something to their attention. It’s similar to IB on TikTok.
Copycat TikTok. I hope there's an h/t in their description
— Allie! Ally! Allé!👩🏽💻🥃🔮✨ (@allieiswriting) September 30, 2020
Tyler Herro is really that young 🤯
(h/t @ESPNStatsInfo) pic.twitter.com/0jc5k4CISZ
— ESPN (@espn) October 1, 2020
Yep. Ag sec Sid @MillerForTexas is fisting with Sasha Baron Cohen, the latest in Miller’s long career of proud moments h/t @JohnnieMo pic.twitter.com/EDMsqg9pDR
— Bud Kennedy / #ReadLocal (@BudKennedy) October 1, 2020