Merge pull request #482 from charleshypk/master

Fix typo.

Author: mhegazy

pages/Interfaces.md

@@ -246,7 +246,7 @@ mySearch = function(src: string, sub: string): boolean {
 ```
 
 Function parameters are checked one at a time, with the type in each corresponding parameter position checked against each other.
-If you do not want to specify types at all, Typescript's contextual typing can infer the argument types since the function value is assigned directly to a variable of type `SearchFunc`.
+If you do not want to specify types at all, TypeScript's contextual typing can infer the argument types since the function value is assigned directly to a variable of type `SearchFunc`.
 Here, also, the return type of our function expression is implied by the values it returns (here `false` and `true`).
 Had the function expression returned numbers or strings, the type-checker would have warned us that return type doesn't match the return type described in the `SearchFunc` interface.