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:headfirstlabs.com/Images/postit/about-unselected.gi...
Url ContentGraphics Interchange Format
MIME Type / Internet Media Typeimage/gif
MIME Type image
File Extension.gif
More Details (link to:)Wikipedia: Graphics Interchange Format
Powered by: Very Tiny URL Shortener at https://vturl.net VeryTinyURL

Header

HTTP/1.1 200 OK
Date Tue, 23 Jan 2018 07:42:08 GMT
Server Apache
X-Content-Type-Options nosniff
Last-Modified Tue, 25 Sep 2007 22:15:20 GMT
ETag 1fe0971-64e-43afd12990e00
Accept-Ranges bytes
Content-Length 1614
Cache-Control max-age=0
Expires Tue, 23 Jan 2018 07:42:08 GMT
Content-Type image/gif

Load Info

page size1614
load time (s)0.486441
redirect count0
speed download0
server IP65.212.180.43


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