If you are not sure if the website you want to visit is safe, you can check it out here. Enter the address (url) of the website and see the invisible elements, such as a header or meta data.
site address:img.youtube.com/vi/4EJv-IakJuQ/0.jp...
Url ContentJPEG Image
MIME Type / Internet Media Typeimage/jpeg
MIME Type image
File Extension.jpeg, .jpg
More Details (link to:)RFC 1314
Powered by: Very Tiny URL Shortener at https://vturl.net VeryTinyURL

Header

HTTP/1.1 200 OK
Accept-Ranges bytes
Content-Type image/jpeg
Content-Length 11339
Date Thu, 23 Nov 2017 10:41:39 GMT
Expires Thu, 23 Nov 2017 12:41:39 GMT
ETag 0
X-Content-Type-Options nosniff
Server sffe
X-XSS-Protection 1; mode=block
Age 2826
Cache-Control public, max-age=7200

Load Info

page size11339
load time (s)0.002345
redirect count0
speed download0
server IP216.58.204.142


* all occurrences of the string "http://" have been changed to "htt???/"