hennasingh

When you want to collaborate on a project for the first time, you fork the project and then clone your fork to your PC.
When you clone a repo from github, it automatically adds that address as a remote address for your local project 
and when you later call git push, it pushes your changes to that remote (which is your fork on github, and which is by convention
named as origin). If you call *git remote -v* at this stage on git bash/command you'll see the address of your own fork as remote origin(both for pulling and pushing)

However, when there is a change in the original repo that you forked, the changes won't be reflected in your local
copy, neither in your fork on github. It doesn't help to call git pull or press update on AS, because the default destination for
updating is your fork on github, which is not updated either. 

So, you need to fetch directly from the original repo that you forked. For this, you need to add it as a second remote address.