Which format works for a USB drive on both Windows and Mac?

Format shared drives as exFAT. Both systems read and write it, files over 4 GB are fine, and every TV and camera understands it. The other formats:

• NTFS, the Windows default: a Mac can read it but not write to it without extra software.
• APFS, the Mac default: Windows cannot read it at all.
• FAT32: works everywhere, but no file over 4 GB.

To format: open Disk Utility (Applications → Utilities), pick the drive in the sidebar, click Erase, choose the name and exFAT. Everything on the drive is erased.

Eject before unplugging: click the ⏏ next to the drive in the Finder sidebar, drag its Desktop icon to the Trash, or press ⌘E with it selected. Pulling a drive out without ejecting earns a warning and, occasionally, a corrupted file.