Who operates USDT?

I'm quite interested in the operational background of USDT. Could you tell me who exactly operates this cryptocurrency? Is it a centralized entity or a decentralized network? I'd also like to know about the security measures taken to ensure the stability and trustworthiness of USDT. Is there a regulatory body overseeing its issuance and circulation? Furthermore, what are the key factors that determine the value of USDT and how does it maintain its peg to the US dollar? Understanding these aspects would greatly help me in my investment decisions regarding this cryptocurrency.