These days, it is easy to saturate your internal storage with all the photos you take digitally. A safe and convenient way to store your photos is by using the cloud. For Mac users, Apple Photos and iCloud can sync to babysit your pictures.
Open Apple Photos... Import all pics... Turn on iCloud Photos in Preference... Check "Optimize Mac Storage"
This allows you to stream the photos/thumbnails and retrieve/download the full quality versions when needed. Saving space on your hard drive. Putting those files on an external drive also works. It's always wise to make multiple backups.