How to add screenshot to READMEs in github repository?
Is it possible to place a screenshot in README file in a GitHub repository? What's the syntax?
If you use Markdown (README.md):
Provided that you have the image in your repo, you can use a relative URL:

If you need to embed an image that's hosted elsewhere, you can use a full URL

GitHub recommend that you use relative links with the ?raw=true
parameter to ensure forked repos point correctly.
Check out an example: https://raw.github.com/altercation/solarized/master/README.md
Also, the documentation on relative links in README files: https://help.github.com/articles/relative-links-in-readmes
And of course the markdown docs: http://daringfireball.net/projects/markdown/syntax
Additionally, if you create a new branch screenshots
to store the images you can avoid them being in the master
working tree
You can then embed them using:

Even though there is already an accepted answer I would like to add another way to upload images to readme on GitHub.
More details you can find here
I found that the path to the image in my repo did not suffice, I had to link to the image on the raw.github.com
subdomain.
URL format https://raw.github.com/{USERNAME}/{REPOSITORY}/{BRANCH}/{PATH}
Markdown example 