I have no images in an activated wp theme

images folder is inside theme’s folder.

But relative URLs do not work that way. They are relative to the URL not to the filesystem path. Your problem is here:

<img id="thinker01" src="https://wordpress.stackexchange.com/questions/74779/images/thinker01.png" width="120" height="163" />

If you look at the request (via HttpFox or other means) you will see that the browser is looking for the image at http://your-site.com/images/thinker01.png and not at http://your-site.com/wp-content/themes/your-theme/images/thinker01.png Don’t use relative URLs like that. Give it a complete path as you did with your stylesheet.

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