typo fix

chapters/OOPs!/chapter.md

@@ -59,7 +59,7 @@ class Ball {
 
 We have declared the Ball class header file (the list of ingredients) and now lets get to the cooking part to see what these ingredients can do!
 Please notice the '#include' tag. This is a way to tell the [compiler](http://www.cplusplus.com/doc/tutorial/introduction/ "Compiler introduction on cplusplus.com") ([wikipedia](https://en.wikipedia.org/wiki/Compiler "Wikipedia on compilers")) about any files to include in the implementation file. When the program is compiled these '#include' tags will be replaced by the original file they're referring to.
-The 'if statement' (#ifndef) is a way to prevent the repetition of header files which could easily occur. This is called an [include guard](https://en.wikipedia.org/wiki/Include_guard "Wikipedia on inlcude guards"). Using this pattern helps the compiler to only include the file once and avoid repetition. Don't worry about this now, we'll talk about it later on!
+The 'if statement' (#ifndef) is a way to prevent the repetition of header files which could easily occur. This is called an [include guard](https://en.wikipedia.org/wiki/Include_guard "Wikipedia on include guards"). Using this pattern helps the compiler to only include the file once and avoid repetition. Don't worry about this now, we'll talk about it later on!
 
 We will now create a class for a ball object. This ball will have color, speed and direction properties: it will move accross the screen and bounce against the wall. Some of these properties we will create with randomized attributes but we'll be carefull to create the righ logic for its motion behaviours.