Tether (USDT) is a type of stablecoin, a cryptocurrency designed to maintain a stable value by pegging it to a reserve of assets, in this case, the US dollar (USD). Launched in 2014 by Tether Limited, USDT was created to provide a digital equivalent of traditional fiat currency that could be used for transactions within the cryptocurrency ecosystem while reducing the volatility typically associated with other cryptocurrencies.

For each Tether token issued, there is supposed to be an equivalent amount of USD held in reserve by Tether Limited, providing a 1:1 backing. This peg to the US dollar allows USDT to maintain a relatively stable value, making it suitable for various purposes within the crypto space, such as trading, hedging against market volatility, and providing an easier means of transferring value between different platforms.

Tether is available on multiple blockchains, including Ethereum, TRON, and Omni Layer (a protocol built on top of the Bitcoin blockchain). As an ERC-20 token on the Ethereum blockchain, USDT can be easily integrated with decentralized finance (DeFi) applications and smart contracts.

Although Tether has become one of the most widely used stablecoins, it has also faced controversies and skepticism regarding its reserves and transparency. Despite these concerns, USDT continues to play a significant role in the cryptocurrency ecosystem due to its widespread adoption and utility as a stable store of value.