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docs/reference/control/in-background.md

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+# In Background
+
+Run code in the background as a separate process or thread; for more information on this advanced construct, see [the micro:bit - a reactive system](/microbit/device/reactive).
+
+```
+control.inBackground(() => {
+})
+```
+
+### Example
+
+The example below shows how a background process can be used to display the current value of the global variable `num`, while code (like the `on button pressed` handler) can change the value of the variable.
+
+```
+let num = 0
+control.inBackground(() => {
+    while (true) {
+        basic.showNumber(num, 150)
+        basic.pause(100)
+    }
+})
+input.onButtonPressed("A", () => {
+    num++;
+})
+```
+
+The code below using the `forever` loop is equivalent to the code above
+
+```
+let num = 0
+basic.forever(() => {
+    basic.showNumber(num, 150)
+})
+input.onButtonPressed("A", () => {
+    num++;
+})
+```
+
+### Contention for the LED display
+
+If you have multiple processes that each show something on the LED screen, you may get unexpected results. Try, for example:
+
+```
+basic.forever(() => {
+    basic.showNumber(6789, 150)
+})
+input.onButtonPressed("A", () => {
+    basic.showNumber(2, 150)
+})
+```
+
+### See also
+
+[while](/microbit/reference/loops/while), [forever](/microbit/reference/basic/forever), [on button pressed](/microbit/reference/input/on-button-pressed)
+

docs/reference/control/reset.md

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+# Reset
+
+Reset the BBC micro:bit (as if you pushed the reset button on the back of the device), which causes the program to start again.
+
+```sig
+control.reset()
+```
+