Apple introduced Universal Clipboard in 2016 as a glue that connects what you copy and paste across all your iCloud-linked devices. Copy some text on an iPhone, and you can paste it on a Mac. AirDrop works as a more general case for the same things, but Universal Clipboard is instant and invisible, when it works. (It used to be erratic in my experience; it’s become increasingly rock solid in the last couple of iOS, iPadOS, and macOS releases.)
To use Universal Clipboard, you need to meet Continuity and Handoff requirements. For Continuity that means iOS 10 or later running on an iPhone 5 or later and nearly every iPad model, or nearly all 2012 or later Mac models with macOS 10.12 Sierra or later installed. For Handoff, you need to have Wi-Fi and Bluetooth enabled on all devices you want to use the feature with, they must be signed into the same iCloud account, and they must be within Bluetooth range of one another. That helps ensures proximity and reduces potential privacy incursions and attack surfaces.
Read more at Macworld.com