More » Is.gd Is.gd provides one of the simplest URL shortening experiences by giving you nothing more than a field to input your long link so you can instantly transform into a shorter one. The downside of this approach, however, is that if a user visits your shortened domain without a directory path on the end, they will be directed to a Bitly branded page. Any information in this field gets reported in the Keywords report under Traffic Sources, alongside all the search engine traffic.
That reference number will be unique to that photo and it’s how Instagram knows which photo you require out of the billions they would have on their systems. The customizable part of the URL is case insensitive.
0 or later within the same domain, the file can be found by the tracking service, subject to time considerations. See if you are using Classic Analytics (ga.js) or Universal Analytics (analytics.js).