OTS
OTS has 3 meanings
Open two-seater
OTS stands for "open two-seater," which refers to a two-seat convertible automobile. It is most often used in online forums that revolve around discussing cars.
OTS is an obscure acronym, primarily used only by car enthusiasts when describing the seating layout of a convertible sports car. Anyone who has an uncle who loves cars most likely has heard or seen him use this acronym.
Besides online forums, you may also see it on social media when people post pictures to brag about their cars. Or, you may see it at classic car auctions online or in-person.
Example
I saw an OTS Mercedes for sale and am thinking about buying it
Baseball Slang Quiz: Can you bat 1.000?
OTS is a casual way to let someone know you're about to intentionally switch topics. You'll usually see it in texts, emails, or forum posts, right before someone brings up something unrelated to the current conversation. It's like saying, "By the way…" (BTW) but with a little more self-awareness.
The OTS shorthand helps keep the flow of a conversation clear, especially in long threads or group chats where things can easily go sideways. It emerged alongside other Internet shorthand in the early 2000s, around the same time "OT" became popular on forums and message boards. While OT is more common in formal or moderated online spaces, OTS tends to show up in casual chats and personal conversations, anywhere someone wants to pivot without sounding random.