Bitcoin Hardware wallets are a hot product as they are much secure than traditional software wallets. A Hardware wallet stores the private keys aka your bitcoins on the device itself instead of on your computer in a file. As a result, you reduce the attack surface for a hacker to try and steal your coins.
Even if your computer is compromised with a keylogger and a RAT (Remote Access Tool), if your Bitcoins are secured by one of these hardware wallets your funds will stay safe.
The below video not only goes over the different features between the hardware wallets, but also showcases which wallets are more durable when put to the test.
Read More:
http://themerkle.com/hardware-wallet-comparison-keepkey-vs-trezor-vs-ledger-nano/
