Add links to README

README.md

@@ -3,7 +3,7 @@
 This repository contains materials used in the ISOS datamanagement course from
 April 6th 2017.
 
-It contains the presentatin as well as all notebooks used during the course. 
+It contains the presentation as well as all notebooks used during the course. 
 To open and edit the notebooks, install miniconda and the course environment as 
 described below. Static PDF versions of the notebooks which run without any 
 installation are also included.
@@ -18,7 +18,9 @@ On Unix/Linux use your distros package manager to install git, e.g.:
 ```bash
 apt-get install git
 ```
-On Windows, dowlnload and install from [github](https://git-for-windows.github.io/)
+On Windows, download and install from [github](https://git-for-windows.github.io/)
+
+On Mac OS X, you already have Git coming with the system. But for latest versions, download and install Git from [Git SCM](https://git-scm.com/download/mac)
 
 
 ## Set up an anaconda installation