Updated Checkbox (markdown)

Checkbox.md

@@ -1 +1,23 @@
-WIP
+Checkbox are objects, which sets the value to true or false by clicking on them
+
+Here is a example of how to create a standard checkbox:
+
+````lua
+local mainFrame = CreateFrame("myFirstFrame"):show()
+local aCheckbox = mainFrame:addCheckbox("myFirstCheckbox"):show()
+````
+
+This will create a default button with the size 1 width and 1 height on position 1 1 (relative to its parent frame), the default background is colors.lightBlue, the default text color is colors.black and the default zIndex is 5. The default value is false
+
+Here are all possible functions available for checkbox. Remember checkbox inherit from [object](https://github.com/NoryiE/NyoUI/wiki/Object):
+
+There are currently no unique functions. Everything you need you can see in the [object](https://github.com/NoryiE/NyoUI/wiki/Object) page.
+
+# Examples
+
+````lua
+local mainFrame = CreateFrame("myFirstFrame"):show()
+local aCheckbox = mainFrame:addCheckbox("myFirstCheckbox"):setValue(true):show()
+NyoUI.debug(aCheckbox:getValue()) - returns true
+````
+