I am a newbie for github and started using GITHUB for WINDOWS chosen private repositories and shared the same with my colleagues.

Now we are experiencing a problem, not sure how to solve it. We tried google and no use.

Myself and a colleague worked on a same file at a same time, he committed before me. I like to know the changes he made and I want to merge his change with my local file and finally want to commit my version. Is it possible with GITHUB using GITHUB for windows? I have done the same before with Tortoise SVN

I Opened shell command prompt and tried something like

  $ git diff

But it shows only differences and not advised me to merge local with staged version ..

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