How do I make certain the gif or pic I am copy pasting is safe?

[ManiacJoe]

3. All the chars are

the JPG converted to encoded text so that the image is physically contained in the HTML file instead of being referenced by an IMG tag as a separate file.

The suffix would probably be the file extension - GIF, JPG and the like. This normally identifies what kind of file it is. The catch with sites like iStockPhoto.com is that they are not going to feed you an image file ID-ed as such until you formally press the buy or download button. Until then they will have the browser download the image file as "data only" using the WEBP file to create the image data using server-side scripting based on all the parameters after the "?" marker in the URL.