This article explains AirDrop and how it's used.
What is AirDrop? What Does That Mean?
AirDrop is a feature in iOS and macOS that lets physically close Mac and iOS devices share files wirelessly with one another with a minimum of fuss. The name basically means to send or 'drop' files over the air from one device to another.
It uses Bluetooth and Wi-Fi to transmit the files via a proprietary, close-range wireless communication process. Those can be text, image, or other types of files, such as playlists and locations. There are no size limits on the file.
You can share between different operating systems (iOS to macOS, for example) or between devices using the same operating system (iOS to iOS, for instance).
How AirDrop Is Used
Often when you want to share photos with someone, you'll either text it or email it. While that will work, it can be much faster to just use AirDrop to send the picture(s) to them. The only requirements are that both devices are from Apple and the devices are in close proximity to one another.
AirDrop isn't just for photos. You can use it to transfer almost anything that you can share. For example, you can AirDrop a website from your iPad to your friend's phone, which is great if they want to bookmark it to read later.
You can also AirDrop text from Notes to someone else's iPad or iPhone. The feature can even handle information like playlists, contact information, and locations you've pinned in Apple Maps.
These instructions apply to devices running iOS 7 or later and post-2012 Macs running OS X Yosemite and newer.
How Does AirDrop Work?
AirDrop uses Bluetooth to create a peer-to-peer Wi-Fi network between the devices. That means you don't need to be connected to your router or even the internet in order to have an AirDrop connection. You do have to have Wi-Fi and Bluetooth turned on, however.
Each device creates a firewall around the connection and files are sent encrypted, which actually makes it safer than transferring via email. AirDrop will automatically detect nearby supported devices, and the devices only need to be close enough to establish a good Wi-Fi connection, making it possible to share files across several rooms.
One advantage to AirDrop is the use of Wi-Fi to make the connection. Some apps provide a similar file sharing capability using Bluetooth. And some Android devices use a combination of Near Field Communications (NFC) and Bluetooth to share files. But both Bluetooth and NFC are relatively slow compared to Wi-Fi, which makes sharing larger files using AirDrop much faster and more convenient.
If you're having troubles with AirDrop not working correctly, try these troubleshooting tips to get it working again.