Typo correction

Author: imanuelcostigan

README.md

@@ -18,7 +18,7 @@ Only the most basic functionality is currently present. In the next year, we hav
 
 Your tests are organized into a simple hierarchy. Each `XCTestCase` subclass has a set of `test` methods, each of which should test one part of your code.
 
-You can find all kinds of useful information on using XCTest in [Apple's documenation](https://developer.apple.com/library/mac/documentation/DeveloperTools/Conceptual/testing_with_xcode/chapters/03-testing_basics.html).
+You can find all kinds of useful information on using XCTest in [Apple's documentation](https://developer.apple.com/library/mac/documentation/DeveloperTools/Conceptual/testing_with_xcode/chapters/03-testing_basics.html).
 
 The rest of this document will focus on how this version of XCTest differs from the one shipped with Xcode.