Images have their own url, and images are displayed in web pages by embedding an image’s URL with some HTML code.
If I wanted to find a picture of a cat, and I typed it in Google, then I wouldn’t know for certain that those images have a creative commons license, and are available for reuse with citation of sources.
I recommend using either Wikimedia Commons, Flickr’s Creative Commons, or Photobucket Creative Commons. If you need a picture from a source other than these three, be sure to give credit to the source.
For example, I really like this picture of this cat: http://commons.wikimedia.org/wiki/Felis_silvestris_catus#mediaviewer/File:Tabby_Pfaffengrund.JPG
You can tell this is the Image URL, and not the website’s URL because it ends with an image file extension: JPG–others are PNG, TIFF, JPEG, etc.
It’s too big to put in a timeline display, so we can select a smaller size to link to:
Click the Download button (1) and then select a smaller version of the image (2). For this example I will choose Small.
Then click the link below the green box, that says “View in browser.”
This will open the image URL in a refreshed page. It will show the smaller version of your image, and the URL will have the adjusted size reflected in it.
If you are linking to the image URL for your blog post you can click “Add Media” and then on the left there will be a menu to select your uploading options. Click “Insert from URL,” and then paste it into the box it provides you.
It will also allow you to change alignment, and add a caption like you normally would when uploading an image to the media library.