And remember to use a different external drive for backup.
4: Network-Attached Storage
You can buy a Network-Attached Storage (NAS) device, install one or more hard drives inside, and connect it to your router. Thus you can access your files over your network. Most modern NAS systems also provide a private cloud, so you can access your data over the Internet, as well.
An NAS will probably be faster and more convenient than an external drive--once it's working properly. But it will almost certainly be more expensive and more difficult to set up and if you work remotely, access to files will be problematic.
5: Buy a large SSD
Yes, they're expensive--about $300 for 960GB as I write this. But this is the fastest and simplest solution.
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