Using a Trezor Wallet involves a combination of hardware security and software interface interaction. When you initiate a transaction, the unsigned transaction data is sent to the hardware device, where it is signed internally using your private keys. The signed transaction is then sent back to the computer and broadcast to the blockchain.

This process ensures your private keys never leave the device, never touch the internet, and never become exposed to your computer or browser. Essentially, Trezor acts as a secure vault that verifies and signs each action you take while keeping your sensitive information shielded.