It’s not possible to upgrade the storage in Macs, so it’s a good idea to buy an external drive to provide extra storage for all your work files, photos, videos, and games. And, of course, you should always have an external drive available for making Time Machine backups in case anything ever goes wrong.
The best choice for you will depend on how much storage you want and how much you are willing to spend. Solid-state drives (SSDs) are the best option as they’re fast, reliable, and compact. Hard drives on the other hand are slower, but you get a lot more storage for your money. If a SSD sounds like it meets your needs, read Best external SSD for Mac. Otherwise read on to find the best hard drives we have tried with our Macs.
Read more at Macworld.com