● Network server or NAS device: If you need to copy files between several Macs on a network, it may be better to use a dedicated server or NAS (network-attached storage) device as an intermediary. (Or, instead of copying files locally, you can access the files directly on the server or NAS. This requires a fast network.)
● Target Disk Mode: The fastest option for moving huge files around occasionally is Target Disk Mode over a Thunderbolt connection between two Macs. The setup differs between Intel-based Macs and Macs with Apple silicon, but once one Mac is in Target Disk Mode, it appears in the Finder of the connected Mac as an external drive, and you can drag files to and from it. It’s most appropriate for transferring many gigabytes of files.
● External storage: Never underestimate the speed and ease of copying files to external storage, whether an SSD, hard drive, or USB flash drive, and then copying them off to another Mac.
● Cloud storage service: Box, Dropbox, Google Drive, and iCloud Drive can all work well for moving files between Macs, although they’re best used with files under a few hundred megabytes. For sharing among your Macs, they’re particularly convenient, and it’s usually easy to copy a link to a file to share it with someone else, though that sometimes requires setting sharing permissions first. iCloud Drive sometimes has problems updating quickly.
● File sending service: The best way to send a large file via email, Messages, or another messaging service is to send a link. That’s easy if the file is already in a cloud storage service, and some email apps and services automatically create links for attachments over a certain size. Otherwise, try a file sending service such as Files to Friends or WeTransfer, which email links to files up to 1–2 GB in size for free. Many other services exist but allow only smaller files for free.
With so many options, you should have no trouble finding one that meets your needs in any particular situation.