Hardware wallet is a physical device that you can plug in to your device. It is very safe as you can use it offline to generate Public keys. It requires a little bit of technical knowledge how to use it properly as you are responsible for making updates of it. It also comes with some additional features, such as connecting it to DeFi. It is probably one of the safest ways of storing your cryptos.
Hardware wallets can be used with Software wallet to secure it. The hardware wallet will be used as a way of confirming transactions. It is useful when the wallet you use does not support the blockchain the crypto you are trying to buy is.
Also, when the company, that created the wallet goes bust, you will still be able to recover your cryptocurrencies thanks to EIP39 standard