How does Tether (USDT) really works?

[mamun777]

Hope this is the right section to post my question.

I understand basic concepts of 1 USDT = 1 USD and backed by 1$ in Tether account, but what confuses me is how USDT token really works. All I was able to find was that it uses "omnylayer" and "all transactions of Tether are bitcoin transaction". What I am interested in is following:
1. Does Tether have it's own blockchain or uses Bitcoin Blockchain?
2. What happens if I sell my BTC for Tether, and then Withdraw it? What asset will be in my wallet? BTC? Tether? BTC's marked as redeemable for Tether?
3. When I send Tether to another Tether user, transaction being processed by BTC blockchain, meaning I'm really sending BTC's. Why can't I deposit Tethers as BTCs? Who holds private key that signs tether transactions?
4. How Tethers are being issued? I mean if price of 1 USDT fixed to be 1 $ they have to "print" tethers and follow it's circulation between users. But how the hell is this possible if it all build on top of BTC blockchain.

Anyway - I would be thankful if someone could point me to whitepaper or article, explaining Tether in as much technical details as possible.

[jonathancool220]

1. Does Tether have it's own blockchain or uses Bitcoin Blockchain?
2. What happens if I sell my BTC for Tether, and then Withdraw it? What asset will be in my wallet? BTC? Tether? BTC's marked as redeemable for Tether?
3. When I send Tether to another Tether user, transaction being processed by BTC blockchain, meaning I'm really sending BTC's. Why can't I deposit Tethers as BTCs? Who holds private key that signs tether transactions?

Tether it uses network or blockchain from OMNI and you can see it in coinmarketcap.
And you can check all the Tether transactions here: https://www.omniexplorer.info/asset/31

ref  : https://coinmarketcap.com/currencies/tether/