@David ******
A border bounce is where you typically cross a land border in to another adjacent country and re enter Thailand (perhaps the same day). You’re re stamped for 30 days and can extend once.
A “visa run” is where you travel to a nearby embassy or consulate and buy a tourist visa before entering Thailand to get a 60 day stay, again extendable once for 30 days.
Visa exempt entries via a land border are limited to two entries in a calendar year. No technical limit via air but you’re not going to able to do as such long term before an immigration officer pulls you up and says no more.