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docs/reference/radio/send-number.md

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+# Send Number
+
+Broadcasts a number data packet to other micro:bits connected via ``radio``.
+
+## Important Security Consideration
+
+The functions in the ``radio`` namespace allow the BBC micro:bit to communicate with other micro:bits.
+
+This API does not contain any form of encryption, authentication or authorization. It's purpose is solely for use as a teaching aid to demonstrate how simple communications operates, and to provide a sandpit through which learning can take place.
+
+For serious applications, BLE should be considered a substantially more secure alternative.
+
+```sig
+radio.sendNumber(0)
+```
+
+### Parameters
+
+* packet - a number to be transmitted.
+
+### Examples
+
+Broadcasts the value of ``acceleration`` x to other micro:bits.
+
+```blocks
+input.onButtonPressed(Button.A, () => {
+    radio.sendNumber(input.acceleration(Dimension.X))
+})
+```
+
+### See also
+
+[receive number](/microbit/input/receive-number), [on data received](/microbit/reference/radio/on-data-received)
+