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docs/reference/radio/receive-number.md

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+# Receive Number
+
+Reads the next radio packet if any and returns the first number.
+
+## 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.receiveNumber()
+```
+
+### Return value
+
+* the first number [number](/microbit/reference/types/number) of the packet if any. `0` otherwise.
+
+### Examples
+
+Read the number broadcasted by other micro:bits.
+
+```blocks
+radio.onDataReceived(() => {
+    led.plotBarGraph(radio.receiveNumber(), 1023);
+})
+```
+
+### See also
+
+[receive number](/microbit/input/receive-number), [on data received](/microbit/reference/radio/on-data-received)
+