Add conditionals rules

Author: CristinaSolana

manual/en-US/coding-standards/chapters/javascript.md

@@ -332,15 +332,26 @@ $('.someElement')
 ```
 
 ### Hoisting
+## Conditional Statements
 
-// TODO
+Use ternary syntax if:
 
+- One condition
+- Result of either evaluation is one operation. 
 
-// TODO
+```
+joomlaRocks ? 'This is true' : 'else it is false';
+```
 
-## Conditional Statements
+Otherwise, use standard syntax:
 
-// TODO ternary/with braces
+```
+if ( condition ) {
+	// statements
+} else {
+	// statements
+}
+```
 
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