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:ndus.edu/images/ndus.gi...
site title:
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
Content-Type image/gif
Last-Modified Tue, 22 Nov 2016 11:08:59 GMT
Accept-Ranges bytes
ETag fdbcf4d2b044d21:0
Server Microsoft-IIS/8.5
X-Powered-By ASP.NET
Date Tue, 22 May 2018 01:59:25 GMT
Content-Length 4543

Load Info

page size4543
load time (s)0.70993
redirect count0
speed download0
server IP216.147.167.67


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