Bad Characters in File Name 2. Missing or Incorrect Suffixes 3. Improper HTML 4.
Web browsers rely on the image's filename to know what sort of image it is.
If a filename doesn't include a suffix, the browser doesn't know what sort of file it is and ignores it. If a filename includes multiple periods, the browser looks only at the last suffix. And it will not display. If the file really is in the GIF format, it should display. If it is actually in another format, like JPEG, the browser will try to display the JPEG file as a GIF, and fail.