Update typeGuard.md

Author: basarat

docs/types/typeGuard.md

@@ -2,7 +2,12 @@
 * [User Defined Type Guards](#user-defined-type-guards)
 
 ## Type Guard
-Type Guards allow you to narrow down the type of an object within a conditional block. TypeScript is aware of the usage of the JavaScript `instanceof` and `typeof` operators. If you use these in a conditional block, TypeScript will understand the type of the variable to be different within that conditional block. Here is a quick example where TypeScript realizes that a particular function does not exist on `string` and points out what was probably a user typo:
+Type Guards allow you to narrow down the type of an object within a conditional block. 
+
+
+### typeof
+
+TypeScript is aware of the usage of the JavaScript `instanceof` and `typeof` operators. If you use these in a conditional block, TypeScript will understand the type of the variable to be different within that conditional block. Here is a quick example where TypeScript realizes that a particular function does not exist on `string` and points out what was probably a user typo:
 
 ```ts
 function doSomething(x: number | string) {
@@ -14,6 +19,8 @@ function doSomething(x: number | string) {
 }
 ```
 
+### instanceof
+
 Here is an example with a class and `instanceof`:
 
 ```ts