Another social media step

I decided to try to set up some of my (or Mark's) photos via Flickr.  Originally, I thought I would add Instagram, but, after reading about both, I decided Flickr was my next step.  I hope folks let me know about both social media tools--which you use, prefer and why.

Here's the link to my gallery:  http://www.flickr.com/photos/99167910@N04/