There are different types of storage, along your digital workflow:
- Storage for files "Work in Progress" - Should be your internal HDD
- Storage for finished files, exports, uploads - Internal or external HDD, just a different one from "WiP"
- Storage for copies of your RAW files / JPG files as they come from camera - Could be an external NAS
- Storage for backup files - A different storage media, e.g. USB drives. Only used fro backup, then store somewhere (dry cabinet? drawer?)
Just some ideas .. Define your workflow, then decide:
- How much data loss can you tolerate? Which data could you afford to lose, which not?
- How quick do you want to have everything back?
- How much tech-savvy are you? The less you are the more you should focus on standard solutions offered in the market (e.g. NAS appliances). If you have time and mood, built your own home server Linux is recommended here.