AirDrop is a feature in Apples iOS and macOS operating systems that allows users to wirelessly transfer files among supported Macintosh computers and iOS devices by means of close-range wireless communication. AirDrop uses a combination of Wi-Fi and Bluetooth to transfer files, and both must be turned on to use AirDrop. To use AirDrop, users need to be signed in with their Apple ID, and transfers are encrypted for security.

Here are the steps to use AirDrop on an iPhone or iPad:

1. Open an app, then tap Share or the Share button.
2. Tap the AirDrop button.
3. Tap the AirDrop user that you want to share with. If you dont see the person you want to share with, make sure they have AirDrop turned on and are within Bluetooth and Wi-Fi range.
4. If you see a red numbered badge on the AirDrop button, there are multiple devices nearby that you can share with. Tap the AirDrop button, then tap the user that you want to share with.
5. For most apps, if you tap Accept, the AirDrop will come through within the same app it was sent from. For example, photos appear in the Photos app and websites open in Safari. App links open in the App Store so you can download or purchase the app. If you AirDrop something to yourself, like a photo from your iPhone to your Mac, it will automatically get sent to your device. Just make sure that both devices are signed in with the same Apple ID.

To adjust AirDrop settings, users can go to Settings, then tap General. From there, users can choose who can see their device and send them content in AirDrop. The options for controlling AirDrop discovery by other devices include:

• No one can see the device (AirDrop disabled)
• Only contacts can see the device
• Everyone can see the device.

In summary, AirDrop is a wireless file transfer feature available on Apple devices that allows users to share photos, videos, websites, locations, and more with other nearby devices.