Do you ever heard of PLACEHOLD.IT ?
What’s PLACEHOLD.IT ? A quick and simple image placeholder service. How does it work?
Just put your image size after our URL and you’ll get a placeholder.
Like this: http://placehold.it/350x150
You can also use it in your code, like this:
<img src="http://placehold.it/350x150">
You will get a image placeholder like below:
But markdown does not support defining the height and width for the image.
so you can choose to use <image> tag if need.
Is it very simple and useful? Have fun!