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docs/reference/logic/if.md

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+# If
+
+Run code based on a condition. #docs #if #then #else #endif #language #elseif
+
+### @parent blocks/language
+ 
+
+Conditionally run code depending on whether a [Boolean](/microbit/reference/types/boolean) condition is true or false.
+
+### Block Editor
+
+![](/static/mb/hourofcode-0.png)
+
+In the Block Editor, click on the dark blue gear icon (see above) to add an *else* or *if* to the current block.
+
+### Example: adjusting screen brightness
+
+![](/static/mb/blocks/game-library/pic0.png)
+
+If the screen [brightness](/microbit/reference/led/brightness) is `< 100`, this code sets the brightness to `255`:
+
+### Lessons
+
+[love meter](/microbit/lessons/love-meter), [zoomer](/microbit/lessons/zoomer)
+
+### See also
+
+[while loop](/microbit/reference/loops/while), [for](/microbit/reference/loops/for), [boolean](/microbit/reference/types/boolean)
+