Is a brand of hardware-based cryptowallets made by SatoshiLabs. During their time, they released two products Trezor Model T and Trezor One. Trezor One is their first product with proud proclamation of being the first hardware-based cryptowallet on the market (citation needed). Nowadays it serves as a lower-end product with Trezor Model T replacing it as their flagship device, with upgraded features and hardware.
Trezor also maintains a firmware called Trezor Core and a cryptographical suite called Trezor Crypto
Aside from that they also develop a software wallet called Trezor Suite, which also serves as a companion app to their devices. The software allows user to update their devices, manage associated wallets and backups. There is also a more lightweight software offered called Trezor Wallet, feature-wise it is similar to Suite, but it has wider support of cryptocurrencies.
Usability info
Their primary source of guidance and information is their wiki and social media/support listed out here:
One thing that stands out from other manufacturers is that they don’t prefer to use classical manuals and instead opt for video guides and wiki.